Long-tail of email infrastructure — 2026-07-26

Deep-dive into the Unknown / Generic MX bucket — the deliverability reality outside the Google / Microsoft monoculture.

At a glance

Unknown / Generic11.27%75 252 domainsUnique unmatched MX36 904individual hostnamesSelf-hosted22.75%151 934 domains

What is this report?

Most landing-page summaries focus on the head of the distribution — Google Workspace, Microsoft 365, Yandex 360. About one in four domains in the Tranco top-1M lives outside that head: regional hosters, self-built Postfix/Exim, niche ESPs, corporate on-prem gateways. This is where most deliverability surprises actually happen. This page surfaces the raw long-tail so security researchers, deliverability teams and dictionary maintainers can mine it.

Top 1000 most common unmatched MX hosts

Sorted by number of domains using each. This is the practical feed-list — every entry near the top is a candidate for inclusion in our dictionaries/mx_providers.py. CSV download covers all 1000.

#	MX target	Domains
1	localhost	487
2	mx.services	280
3	mail	244
4	zonemx.eu	195
5	mail.parktons.com	169
6	mail1.sbnation.com	168
7	mail2.recop.jp	147
8	alltheemails.com	145
9	mail.autoline.com.ua	144
10	mx2.z-ns.net	143
11	mx.email-messaging.com	143
12	mx1.ticketsinbound.com	127
13	lbmx.bcc.gov.bd	126
14	~	123
15	mxi.alpha-prm.jp	123
16	mx2.ticketsinbound.com	123
17	mx1d10.thinline.cz	108
18	mx1b20.thinline.cz	108
19	cloudmail.auto-vision.ru	99
20	s.mail.dcsaas.net	95
21	mx.maxns.net	91
22	mailforward.dnsv.jp	87
23	mx-backup.serveriai.lt	86
24	amazon-smtp.amazon.com	85
25	mx1-dk.centerasecurity.dk	83
26	mx2-dk.centerasecurity.dk	83
27	mail.pickelhost.com	78
28	mx-01.mail-forwarder.io	78
29	mx1.netim.net	77
30	mx2.netim.net	77
31	mx3-dk.centerasecurity.dk	77
32	mail.global.frontbridge.com	76
33	mx-02.mail-forwarder.io	76
34	mx.vshosting.eu	76
35	mail-fr.securemail.pro	75
36	void.blackhole.mx	74
37	mx1.email-cluster.com	74
38	mx2.email-cluster.com	74
39	failover1.email-cluster.com	71
40	mx.sendcloud.org	70
41	mx.spamfilter.io	70
42	email.webglobe.cz	70
43	email2.webglobe.cz	70
44	mx.aams4.jp	69
45	email3.webglobe.cz	69
46	email4.webglobe.cz	69
47	mx6.kvnbw.de	69
48	mx7.kvnbw.de	69
49	mx8.kvnbw.de	69
50	mx9.kvnbw.de	69

Show rows 51 – 1000

#	MX target	Domains
51	q01es.mail.s-web.de	69
52	q02es.mail.s-web.de	69
53	r01es.mail.s-web.de	69
54	r02es.mail.s-web.de	69
55	mxa.expediagroup.com	68
56	mxb.expediagroup.com	68
57	gmail22.gadmail.de	67
58	gmail23.gadmail.de	67
59	wmail22.gadmail.de	67
60	mx1.nepal.gov.np	67
61	mx-0.aams4.jp	66
62	mx-1.aams4.jp	66
63	wmail23.gadmail.de	66
64	mx2.nepal.gov.np	66
65	mail.mpcloud.net	65
66	smtp-avas.seeweb.it	65
67	antispam.korea.kr	65
68	mx4.emailowl.com	64
69	mail.vipmailservice.com	64
70	mx5.emailowl.com	63
71	smtp.faisco.cn	63
72	mx01.statens-it.dk	63
73	mx02.statens-it.dk	63
74	mx03.statens-it.dk	63
75	mx04.statens-it.dk	63
76	mx05.statens-it.dk	63
77	mx06.statens-it.dk	63
78	mx07.statens-it.dk	63
79	mx08.statens-it.dk	63
80	omail22.gadmail.de	63
81	omail23.gadmail.de	63
82	rmail22.gadmail.de	63
83	rmail23.gadmail.de	63
84	posta.mediacenter.hu	62
85	posta2.mediacenter.hu	62
86	posta4.mediacenter.hu	62
87	posta5.mediacenter.hu	62
88	mx1.oderland.com	62
89	mx2.oderland.com	62
90	mx6.emailowl.com	62
91	mx1.daouoffice.com	62
92	posta3.mediacenter.hu	61
93	mx1.simplelogin.co	60
94	mx2.simplelogin.co	60
95	townsites.dnsmaster.net	59
96	spamexpert01.host.bg	59
97	spamexpert02.host.bg	59
98	d01es.mail.s-web.de	59
99	d02es.mail.s-web.de	59
100	e01es.mail.s-web.de	59
101	e02es.mail.s-web.de	59
102	mx01.muumuu-mail.com	58
103	generalsmtp.disney.com	57
104	mx.mymailwall.com	57
105	glacier-relay.mxrouting.net	56
106	mx3.oderland.com	56
107	mx4.oderland.com	56
108	mta.vshosting.eu	56
109	glacier.mxrouting.net	55
110	mx-1.mail.go.id	55
111	mx-2.mail.go.id	55
112	mx1.alwaysdata.com	55
113	mx2.alwaysdata.com	55
114	mx2.daouoffice.com	55
115	antispam.tebilisim.com	54
116	mx-3.mail.go.id	54
117	mx-4.mail.go.id	54
118	mx1.1984.is	53
119	mail.univalence.com	53
120	mx-mibc-fr-11.mailinblack.com	53
121	mx2.1984.is	52
122	mx4.nameshield.net	52
123	mx1.netsolmail.net	52
124	mx01.easyname.eu	52
125	mx02.easyname.eu	52
126	mail2.careerjet.net	52
127	mx-n.global-mail.cn	51
128	mx.otenet.gr	51
129	mailgw01.host.it	51
130	mxwcom.263xmail.com	50
131	mx01.cbsolt.net	50
132	mx02.cbsolt.net	50
133	mx2.mijndomein.nl	50
134	adresseavisen.in.tmes.trendmicro.eu	50
135	mailgw02.host.it	50
136	mx2.smtp.goog	50
137	mx3.smtp.goog	50
138	mx4.smtp.goog	50
139	mail.twincdn.com	50
140	mail.bluetie.com	49
141	mxcom.263xmail.com	49
142	mail2.no-ip.com	49
143	mx1.mijndomein.nl	49
144	mx1.smtp.goog	49
145	y01es.mail.s-web.de	48
146	y02es.mail.s-web.de	48
147	mx1-n.global-mail.cn	48
148	c1.liara.email	48
149	wednesday.mxrouting.net	48
150	p.webcom.ctmail.com	48
151	mail.idp365.net	48
152	g01es.mail.s-web.de	48
153	g02es.mail.s-web.de	48
154	z01es.mail.s-web.de	48
155	z02es.mail.s-web.de	48
156	mail1.no-ip.com	47
157	wednesday-relay.mxrouting.net	47
158	mx4.otenet.gr	47
159	mx2.otenet.gr	47
160	mg.g-cloud.by	47
161	mx01.glesys.se	47
162	ni-spamexperts.guzel.net.tr	46
163	mail02.mail-gw.de	46
164	mail03.mail-gw.de	46
165	mx3.otenet.gr	45
166	mx1.bund.de	45
167	relay.exohosting.sk	45
168	mail.mailhub.work	44
169	mx1.mythic-beasts.com	44
170	mx2.mythic-beasts.com	44
171	mail.valtori.fi	44
172	mx02.glesys.se	44
173	mx2.bund.de	44
174	webmail3.terrawan.eu	44
175	mxc.global-mail.cn	44
176	mars.intermailgate.com	44
177	mx1.tigertech.net	43
178	mx2.tigertech.net	43
179	mx3.tigertech.net	43
180	mx1.supremebox.com	43
181	mx2.supremebox.com	43
182	heracles.mxrouting.net	43
183	mxu.global-mail.cn	43
184	mail1.correo.gob.es	42
185	mail2.correo.gob.es	42
186	mx.noris.net	42
187	relay2.dnsserver.eu	42
188	cloudmail01.clausweb.ro	41
189	cloudmail02.clausweb.ro	41
190	cloudmail03.clausweb.ro	41
191	cloudmail04.clausweb.ro	41
192	mx1.webhouse.sk	41
193	mx2.webhouse.sk	41
194	mx3.webhouse.sk	41
195	mxpool.de2.hostedoffice.ag	41
196	heracles-relay.mxrouting.net	41
197	a1.spambusters.email	41
198	n1.spambusters.email	41
199	mx2.postmaster.hu	41
200	smtp-in-internet-usr-m.gslb.srv.bnpparibas	41
201	mx.cstnet.cn	41
202	relay1.exohosting.sk	41
203	relay3.dnsserver.eu	41
204	mail1.digikey.com	41
205	mail2.digikey.com	41
206	mail3.digikey.com	41
207	mx.stable.cz	40
208	mx100.ucozmail.com	40
209	mx1.pokingbear.com	40
210	mx2c51.megamailservers.eu	40
211	mxs.ht-systems.ru	40
212	mail-in.fruugo.net	40
213	mx.siteprotect.com	39
214	mxmail.icoremail.net	39
215	mx1.tmdhosting.com	39
216	mx2.tmdhosting.com	39
217	eu-esec-01.heimdalsecurity.com	39
218	eu-esec-02.heimdalsecurity.com	39
219	smtp-avas-th.seeweb.it	39
220	mx1.us.opalstack.com	39
221	mx2.us.opalstack.com	39
222	inbound.postmarkapp.com	39
223	mail.mystoredns.com	39
224	offline.iserv.eu	39
225	fusion.mxrouting.net	38
226	fusion-relay.mxrouting.net	38
227	mx1.daringibex.com	38
228	mx1.dnsmadeeasy.com	38
229	mx2.dnsmadeeasy.com	38
230	mail.dms.unileverservices.com	38
231	mail2.mystoredns.com	38
232	1-grid-mx02.com	37
233	1-grid-mx03.co.za	37
234	1-grid-mx01.co.za	37
235	wmx.ecounterp.com	37
236	mx10.active24.cz	37
237	mx20.active24.cz	37
238	fakemx.noris.net	37
239	mail.gigaserver.cz	37
240	mail.bayern.de	37
241	mx01.tophost.ch	37
242	france.security-mail.net	37
243	europe.security-mail.net	37
244	semail.sandhills.com	37
245	wemail.sandhills.com	37
246	1-grid-mx04.com	36
247	mx1.krystal.io	36
248	mx2.krystal.io	36
249	arrow.mxrouting.net	36
250	mx-10.au-east.atmailcloud.com	36
251	mx-20.au-east.atmailcloud.com	36
252	mt-spamexperts.guzel.net.tr	36
253	mxs.armgs.team	36
254	mx1.nz.smxemail.com	36
255	assur.rtl.de	36
256	marduk.rtl.de	36
257	sul.rtl.de	36
258	sulis.rtl.de	36
259	mx01.ergonet.it	36
260	mx02.ergonet.it	36
261	mx03.ergonet.it	36
262	mx04.ergonet.it	36
263	mx.stable.sk	36
264	mx.noris.de	36
265	mx-mibc-fr-06.mailinblack.com	36
266	pri-jeemsg.eemsg.mail.mil	36
267	sec-jeemsg.eemsg.mail.mil	36
268	chocobo.mxrouting.net	36
269	mail.makeup.com.ua	36
270	zc-mx.zohocorp.com	36
271	zc-mx2.zohocorp.com	36
272	zc-mx3.zohocorp.com	36
273	tuesday.mxrouting.net	36
274	tuesday-relay.mxrouting.net	36
275	mail4.makeshop.jp	35
276	mx.getcourse.ru	35
277	mx02.tophost.ch	35
278	mx3.dnsmadeeasy.com	35
279	mx1.daemonmail.net	35
280	mx2.daemonmail.net	35
281	mx.easymail.ca	35
282	mx.renr.es	35
283	chocobo-relay.mxrouting.net	35
284	fbm-mail-01.beanonetwork.com	35
285	mailbox.wargaming.net	35
286	mx1.mailer91.com	34
287	mx4.webhouse.sk	34
288	mx5.webhouse.sk	34
289	mx6.webhouse.sk	34
290	mail.techsurgeons.com	34
291	shadow.mxrouting.net	34
292	mmxs.majordomo.ru	34
293	mx1.emailowl.com	34
294	arrow-relay.mxrouting.net	34
295	ntvirus.url.com.tw	34
296	pmg.prodestek.com.tr	34
297	blizzard.mxrouting.net	34
298	mx.ms.bi.zone	34
299	mail-8.mtpserver.net	34
300	mail-12.mtpserver.net	34
301	mail-13.mtpserver.net	34
302	mail.lima-city.de	33
303	mx2.mailer91.com	33
304	cnc.biz-email.net	33
305	ntvirus2.url.com.tw	33
306	mx1.mas.t-systems-service.com	33
307	mx2.nz.smxemail.com	33
308	mx1.loading.es	33
309	mx2.loading.es	33
310	mx3.loading.es	33
311	mail73.conoha.ne.jp	33
312	us1-smtp-mx1.titanhq.com	33
313	mail.swisscom.com	33
314	mail10.swisscom.com	33
315	mail20.swisscom.com	33
316	mail.variomedia.de	33
317	mail.nhs.uk	33
318	eu1-smtp-mx1.titanhq.com	32
319	shadow-relay.mxrouting.net	32
320	witcher.mxrouting.net	32
321	witcher-relay.mxrouting.net	32
322	mx2.emailowl.com	32
323	mx3.emailowl.com	32
324	mx2.mas.t-systems-service.com	32
325	mx3.mas.t-systems-service.com	32
326	blizzard-relay.mxrouting.net	32
327	us1-smtp-mx2.titanhq.com	32
328	smtp-scan01.mx.reflected.net	32
329	mforward.dtag.de	32
330	smtp.renault.fr	32
331	smtp2.renault.fr	32
332	ssl.emailserver.vn	32
333	mailin100.dcpserver.de	32
334	mx10.vwgroup.com	32
335	mail.lakennetwork.com	32
336	mx01.routing.net	32
337	mx03.routing.net	32
338	mx.x.recruit.co.jp	31
339	redbull.mxrouting.net	31
340	mail-s30.1gb.ru	31
341	mx-mibc-fr-08.mailinblack.com	31
342	mx1.onlinemail.io	31
343	mx2.onlinemail.io	31
344	pixel.mxrouting.net	31
345	mail.biz-email.net	31
346	mx.soverin.net	31
347	mxs.activeby.net	31
348	mmx.mail.gov.az	31
349	mx1.alibaba-inc.com	31
350	mail.joker.com	31
351	mx.claramail.com.br	31
352	echo.mxrouting.net	31
353	inbound01.dynata.com	31
354	inbound02.dynata.com	31
355	inbound03.dynata.com	31
356	mx0002.neo.space	31
357	mx0001.neo.space	31
358	mx02.routing.net	31
359	mail-relay.wetteronline.de	31
360	eu1-smtp-mx2.titanhq.com	30
361	redbull-relay.mxrouting.net	30
362	mail.postale.io	30
363	mx.zohocloud.ca	30
364	a.mx.mayfirst.org	30
365	b.mx.mayfirst.org	30
366	c.mx.mayfirst.org	30
367	mxbackup.wnpower.com	30
368	mx01.espmailservice.net	30
369	alt1.mymailcheap.com	30
370	mx01.agnat.pl	30
371	mxin1.airnet.ne.jp	30
372	mxin2.airnet.ne.jp	30
373	mx.mailo.com	30
374	mx-mibc-fr-07.mailinblack.com	30
375	mx-dor.bell.ca	30
376	mx-wyn.bell.ca	30
377	echo-relay.mxrouting.net	30
378	reply.s12.exacttarget.com	30
379	mail.cmposta.com	30
380	mx0.mail7.freehost.com.ua	30
381	mx1.mail7.freehost.com.ua	30
382	mx2.mail7.freehost.com.ua	30
383	mailgw.nic.in	30
384	mx-mibc-fr-05.mailinblack.com	30
385	aspmx1.dooray.com	30
386	mx10.websupport.se	30
387	sgrmgw5.swatchgroup.com	30
388	sgrmgw6.swatchgroup.com	30
389	mx01.ntc.net.pk	30
390	mail.cm.telia.net	30
391	mx.fimn.net	29
392	mx2.zohocloud.ca	29
393	mx3.zohocloud.ca	29
394	mx-waw.grupawp.pl	29
395	mx-gda.grupawp.pl	29
396	mx1.antispam-login.net	29
397	mx2.antispam-login.net	29
398	alt2.mymailcheap.com	29
399	mx1.friendfinder.com	29
400	mx2.friendfinder.com	29
401	mx3.friendfinder.com	29
402	mx1.heinlein-support.de	29
403	mx2.heinlein-support.de	29
404	mail.voxops.net	29
405	mx1.dandomain.dk	29
406	mx.online.net	29
407	mx1.dfw.automattic.com	29
408	mx2.ams.automattic.com	29
409	mx3.34sp.com	29
410	gatekeeper.space.net	29
411	gatekeeper.spacenet.de	29
412	mxpool.hostedoffice.ag	29
413	email.cnhi.com	29
414	alt2-mx.rackhostmx.com	29
415	mx20.websupport.se	29
416	mailasp.sovcombank.ru	29
417	mx-mibc-fr-10.mailinblack.com	28
418	securemail-mx1.synaq.com	28
419	securemail-mx2.synaq.com	28
420	mail3.makeshop.jp	28
421	mx2.spamfiltering.com	28
422	us1.workspace.org	28
423	pixel-relay.mxrouting.net	28
424	tarbaby.junkemailfilter.com	28
425	inmx.rambler-co.ru	28
426	blackhole.aftermarket.pl	28
427	mx2.dandomain.dk	28
428	mx-cache.online.net	28
429	mx4.34sp.com	28
430	mx-ha.emailemnuvem.com.br	28
431	a2.spambusters.email	28
432	mail2.filteredmx.net	28
433	mx.buzondecorreo.com	28
434	mx2.mailhop.org	28
435	mail.svethostingu.cz	28
436	smtp.dvtech.io	28
437	dmeas13.imail.scig.gov.hk	28
438	dmeas14.imail.scig.gov.hk	28
439	pmeas13.imail.scig.gov.hk	28
440	pmeas14.imail.scig.gov.hk	28
441	corpmx.yelpcorp.com	28
442	mx.viettelidc.com.vn	27
443	aspmx.whoisworks.com	27
444	work-mx.app.hey.com	27
445	mg1.g-cloud.by	27
446	mail-pt.securemail.pro	27
447	mx1.spamfiltering.com	27
448	sns.nethost.sk	27
449	moose.mxrouting.net	27
450	moose-relay.mxrouting.net	27
451	mx-1.pobox.com	27
452	mx-2.pobox.com	27
453	mx1.motosnap.com	27
454	mx2.motosnap.com	27
455	mx3.heinlein-support.de	27
456	mta.hosts.net.nz	27
457	mgp.cybermail.jp	27
458	mail1.filteredmx.net	27
459	mail3.filteredmx.net	27
460	mailgw3.oneoffice.jp	27
461	mx1.fiercebadger.com	27
462	rmx.mailgw.jp	27
463	mx1.paypalcorp.com	27
464	gateway.aos.rw	27
465	mx0162.ppsmtp.com	27
466	mx0162.ppsmtp.de	27
467	mx1.mail-scanner.eu	26
468	mx0.fortion.net	26
469	mx1.krystal.co.uk	26
470	mx-3.pobox.com	26
471	mx.truemail.it	26
472	mgf.cybermail.jp	26
473	sunfire.mxrouting.net	26
474	mxus1.alibaba-inc.com	26
475	mx1.maileroo.com	26
476	mx02.emailpnl.com	26
477	mxs.tbank.ru	26
478	mx03.puc.rediris.es	26
479	mx04.puc.rediris.es	26
480	mx2.paypalcorp.com	26
481	taylor.mxrouting.net	26
482	aws-useast1-mail.mars-inc.com	26
483	my-mx.email-protect.gosecure.net	25
484	alf1.aspmx.whoisworks.com	25
485	alf2.aspmx.whoisworks.com	25
486	mx2.mail-scanner.eu	25
487	mx1.fortion.net	25
488	mx2.krystal.co.uk	25
489	gw-spam.mailwood.com	25
490	safari.mxrouting.net	25
491	hzmx01.xmail.ntesmail.com	25
492	eagle.mxlogin.com	25
493	smtp1-inki.e-i.net	25
494	smtp1-insi.e-i.net	25
495	mx1.earfulwolf.com	25
496	mx1.stsmail.ro	25
497	mx2.stsmail.ro	25
498	email.imcloud.org	25
499	mx2.maileroo.com	25
500	mx1.trustytapir.com	25
501	mx.mailbox.orange-business.com	25
502	mx01.emailpnl.com	25
503	mx01.rto.de	25
504	mx1.progreso.pl	25
505	mx2.progreso.pl	25
506	mx3.progreso.pl	25
507	mx.eivoittoa.fi	25
508	cr1.cylex.de	25
509	mx001.fatsecret.com	25
510	mx2.pokerstars.com	25
511	serwer1429664.home.pl	25
512	mx1.mijn.host	24
513	mx2.mijn.host	24
514	mx2.fortion.net	24
515	mail.hostalo.it	24
516	hzmx02.xmail.ntesmail.com	24
517	mx.spamorez.ru	24
518	smtp1.lerelaisinternet.com	24
519	smtp2.lerelaisinternet.com	24
520	mx.serveriai.lt	24
521	mx-aol.mail.gm0.yahoodns.net	24
522	pmx.megacp.com	24
523	bmx.megacp.com	24
524	inbound.mail.naiadsystems.com	24
525	allegro.in.tmes.trendmicro.eu	24
526	in.widestore.net	24
527	mxh.eu.mpssec.net	24
528	mxi.eu.mpssec.net	24
529	mail-in1.rian.ru	24
530	mail-in2.rian.ru	24
531	smtp.sarenet.es	24
532	mxf.eu.mpssec.net	24
533	mxg.eu.mpssec.net	24
534	mx20.vwgroup.com	24
535	mx1-mailcontrol.conova.com	24
536	mx2-mailcontrol.conova.com	24
537	mx3-mailcontrol.conova.com	24
538	mx4-mailcontrol.conova.com	24
539	mx1.mailhop.us	24
540	parse.mailjet.com	24
541	mx.turkticaret.net	24
542	smx2.web-hosting.com	23
543	mxbackup1.junkemailfilter.com	23
544	mx1.sparkspace.huaweicloud.com	23
545	mx2.sparkspace.huaweicloud.com	23
546	mx-a.secumail.de	23
547	mx-b.secumail.de	23
548	webmail.mail.maxns.net	23
549	mail01.be2.com	23
550	rx1.sparkpostmail.com	23
551	rx2.sparkpostmail.com	23
552	rx3.sparkpostmail.com	23
553	mfwd.ebrandservices.com	23
554	mail.ssonet.nl	23
555	mail2.ssonet.nl	23
556	mail1.ethionet.et	23
557	mail2.ethionet.et	23
558	mail3.ethionet.et	23
559	mail4.ethionet.et	23
560	mgc.cybermail.jp	23
561	safari-relay.mxrouting.net	23
562	mail.websitefa.com	23
563	mx.zoho.jp	23
564	mx2.zoho.jp	23
565	mx3.zoho.jp	23
566	eagle-relay.mxlogin.com	23
567	dmeas11.imail.scig.gov.hk	23
568	dmeas12.imail.scig.gov.hk	23
569	pmeas11.imail.scig.gov.hk	23
570	pmeas12.imail.scig.gov.hk	23
571	sunfire-relay.mxrouting.net	23
572	ezsmtp.bizmeka.com	23
573	mx1.savana.cz	23
574	mx2.savana.cz	23
575	mx1.hostcreators.sk	23
576	mx2.hostcreators.sk	23
577	smx.megacp.com	23
578	mx01.goneo.de	23
579	mx02.goneo.de	23
580	s2vg300mr01.pzd-svn.de	23
581	s2vg300mr02.pzd-svn.de	23
582	mx.turktelekomeposta.com	23
583	mx-in.kommunale.it	23
584	mx1c51.megamailservers.com	23
585	mx1.ravingchamois.com	23
586	mx-in04b.natrohost.com	23
587	mx.usa.net	23
588	mx1.megamailservers.com	23
589	smartmail1.fednet.gov.ae	23
590	smartmail2.fednet.gov.ae	23
591	mxbackup.routing.net	23
592	mx1.mailhop.co	23
593	mx1.mailhop.co.uk	23
594	mx1.promail.com.tr	23
595	mx2.promail.com.tr	23
596	extern-gateway.innogames.de	23
597	mx3.hh.ru	23
598	mx.vps1.8com.cz	23
599	smtp-in0.prod0.webspace.bz	22
600	smtp-in1.prod0.webspace.bz	22
601	smx3.web-hosting.com	22
602	mx.spamservice.nl	22
603	fallbackmx.spamservice.nl	22
604	lastmx.spamservice.nl	22
605	mx1.efwd.spaceship.net	22
606	mx2.efwd.spaceship.net	22
607	mail.sidecloud.cc	22
608	mailx.hoster.ru	22
609	mg.cybermail.jp	22
610	mx1.cloudaccess.net	22
611	mx2.cloudaccess.net	22
612	mx01.servicehoster.ch	22
613	bounce.argewebhosting.nl	22
614	mx1.alastyr.com	22
615	mail.anonaddy.me	22
616	mailscanner01.zoner.fi	22
617	mailscanner02.zoner.fi	22
618	mail1.qlc.co.in	22
619	mail2.qlc.co.in	22
620	mail3.qlc.co.in	22
621	mx1.gigahost.dk	22
622	mx2.gigahost.dk	22
623	mx3.gigahost.dk	22
624	mail.cco.in.ua	22
625	mx.nameweb.biz	22
626	mx.sina.net	22
627	mx3c51.megamailservers.com	22
628	mx-in04.natrohost.com	22
629	mx1.reg365.net	22
630	mx2.reg365.net	22
631	mx2.megamailservers.com	22
632	mx3.megamailservers.com	22
633	mx20.profesionalhosting.com	22
634	smtp1.osuosl.org	22
635	smtp2.osuosl.org	22
636	smtp3.osuosl.org	22
637	smtp4.osuosl.org	22
638	taylor-relay.mxrouting.net	22
639	mx1.suremail.cn	22
640	mx2.suremail.cn	22
641	mx3.suremail.cn	22
642	mx4.suremail.cn	22
643	mx6.hh.ru	22
644	smx1.web-hosting.com	21
645	mx10.omc.net	21
646	mail.endora.cz	21
647	mx.c2.icoremail.net	21
648	mgk.cybermail.jp	21
649	mx02.servicehoster.ch	21
650	mx1.niagahoster.co.id	21
651	mx2.niagahoster.co.id	21
652	mx1.spamorez.ru	21
653	mx2.alastyr.com	21
654	mail2.anonaddy.me	21
655	mx-in03b.natrohost.com	21
656	my.mailbux.com	21
657	mx01.mi.com.co	21
658	mx.c3.icoremail.net	21
659	smtp.sparkpostmail.com	21
660	cmx.yaanimail.com	21
661	pochta.mtw.ru	21
662	cloudscan24.ilger.com	21
663	ag1.cesnet.cz	21
664	ag2.cesnet.cz	21
665	smtp.egcloud.gov.eg	21
666	mxbjm.chinaemail.cn	21
667	mx10.profesionalhosting.com	21
668	sgc.hsplus.email	21
669	mailscanner.powerhosting.dk	21
670	ign-mx1.webglobe.com	21
671	ign-mx2.webglobe.com	21
672	mx1.belwue.de	21
673	mail.tehila.gov.il	21
674	mx01.earthlink-vadesecure.net	21
675	mx02.earthlink-vadesecure.net	21
676	mx03.earthlink-vadesecure.net	21
677	mx04.earthlink-vadesecure.net	21
678	pop2.ocnk.net	21
679	mx01.windstream.net	21
680	mx.shopmania.net	21
681	mail.mycylex.de	21
682	spam.seoul.go.kr	21
683	spam2.seoul.go.kr	21
684	mail.bizboxa.com	20
685	mx.inbox.eu	20
686	mx-in-1.webreus.nl	20
687	mx-in-2.webreus.nl	20
688	mxfallback.spamfilterserver.com	20
689	accor.in.tmes.trendmicro.eu	20
690	mailfilter.hibox.biz	20
691	mx11.omcnet.de	20
692	mx76.antispam-post.ru	20
693	mx-4.pobox.com	20
694	mx-5.pobox.com	20
695	mail2.greennet.org.uk	20
696	monday.mxrouting.net	20
697	mail.academiadasapostas.com	20
698	mx-in03.natrohost.com	20
699	mx1.em.dingtalk.com	20
700	mx2.em.dingtalk.com	20
701	mx1.spatiul.ro	20
702	mx2.spatiul.ro	20
703	mx3.spatiul.ro	20
704	mx4.spatiul.ro	20
705	smtp.tmgrup.com.tr	20
706	captmx-re20.bizflycloud.vn	20
707	captmx-re30.bizflycloud.vn	20
708	captmx-re40.bizflycloud.vn	20
709	mail1.rit.ee	20
710	mail3.rit.ee	20
711	mailas02.clog.jp	20
712	mx01.ofis.net	20
713	mx2.c3.icoremail.net	20
714	mx.xmission.com	20
715	emix.sdv.fr	20
716	fallback.axc.eu	20
717	antispamawn.thaicloudsolutions.com	20
718	gwmail.ktbizoffice.com	20
719	postrelay1.lrz.de	20
720	postrelay2.lrz.de	20
721	mail-de.maxcluster.net	20
722	mail.mizbanfalocal.com	20
723	backup-mx.powerhosting.dk	20
724	ign-mx3.webglobe.com	20
725	ign-mx4.webglobe.com	20
726	ge-smtp01.gammae.com	20
727	a.mx.domainoo.fr	20
728	mail.framasoft.org	20
729	mx1.smashtic.com	20
730	mail.mailnode.cc	20
731	mail2535230.us.to	20
732	mx.vk.com	20
733	sv62.ifastnet11.org	19
734	mx2.lite-host.su	19
735	mx1.chengmail.cn	19
736	mx2.chengmail.cn	19
737	mail.net4india.com	19
738	mx32.antispam-post.ru	19
739	mx1.greenhost.nl	19
740	mx2.greenhost.nl	19
741	mx.portsit.se	19
742	mx.portsit.com	19
743	pmg.guzel.net.tr	19
744	pmg2.guzel.net.tr	19
745	b1234.mx.srv.dfn.de	19
746	c1234.mx.srv.dfn.de	19
747	mail01.phoenixgroup.eu	19
748	mail02.phoenixgroup.eu	19
749	mail03.phoenixgroup.eu	19
750	mail04.phoenixgroup.eu	19
751	reply.s50.exacttarget.com	19
752	mx3.mailinghosting.com	19
753	mail.ap-dev.ru	19
754	mx3.em.dingtalk.com	19
755	mr.pavietnam.vn	19
756	mx.noip.com	19
757	mailgw.mts.rs	19
758	mailf.comsats.net.pk	19
759	mail.mosby.com	19
760	reply.s13.exacttarget.com	19
761	mailin-01.mx.sonic.net	19
762	mailin-02.mx.sonic.net	19
763	mdn.corp-email.cn	19
764	mx1.monarobase.net	19
765	mx2.monarobase.net	19
766	mia1-load.supramail.com.br	19
767	mrelay.axa.com	19
768	mx1.antispam-post.ru	19
769	mail.system.digitalartscloud.com	19
770	mxc.meoempresas.pt	19
771	mxp.meoempresas.pt	19
772	inbound.registeredsite.com	19
773	mx01.govmail.gov.jo	19
774	mx02.govmail.gov.jo	19
775	mx02.ofis.net	19
776	mx-stp.mail.saunalahti.fi	19
777	mx-tnl.mail.saunalahti.fi	19
778	mail.messaging.microsoft.com	19
779	fortispam.cedia.org.ec	19
780	mx01.shopmania.biz	19
781	mx4.eganet.go.tz	19
782	cloudscan25.ilger.com	19
783	gcmx01.govkorea.kr	19
784	gcmx02.govkorea.kr	19
785	gcmx03.govkorea.kr	19
786	mx.junkemailfilter.org	19
787	mx4c51.megamailservers.eu	19
788	friday.mxlogin.com	19
789	mxprimary.spamfilterserver.com	19
790	mx01.mail.alibaba.com	19
791	mx02.mail.alibaba.com	19
792	mail2.p24.hu	19
793	bmx01.neodigit.net	19
794	bmx02.neodigit.net	19
795	mta5.am0.yahoodns.net	19
796	mta6.am0.yahoodns.net	19
797	mta7.am0.yahoodns.net	19
798	inbound-reply.s1.exacttarget.com	19
799	rcmx3.roscongress.org	19
800	mxbackup2.junkemailfilter.com	18
801	mx1.vevida.com	18
802	mx2.vevida.com	18
803	mx3.vevida.com	18
804	backup-mx.vevida.com	18
805	mfwd.eurodns.com	18
806	rk2.comju.de	18
807	smtp-gate.gn.apc.org	18
808	mx.portsit.net	18
809	a1234.mx.srv.dfn.de	18
810	mx01mi.neen.it	18
811	mx02mi.neen.it	18
812	primary.us.etp.fireeyegov.com	18
813	alt1.us.etp.fireeyegov.com	18
814	mgw.gov.kz	18
815	mx-in1.euronic.fi	18
816	mx-in2.euronic.fi	18
817	mx2.auto-vision.ru	18
818	mdn.corpemail.net	18
819	secmail.iap.socgen.com	18
820	mailforward.lcn.com	18
821	m213-mail.server4u.cz	18
822	uk1-smtp-mx1.titanhq.com	18
823	uk1-smtp-mx2.titanhq.com	18
824	vip-mail.superhosting.cz	18
825	mxs.hoster.ru	18
826	mx.fusemail.net	18
827	mxbackup01.ofis.net	18
828	mxbackup1.svrsh.com	18
829	mail.schroederdennis.de	18
830	smtp01.wmaker.net	18
831	smtp02.wmaker.net	18
832	mxabjm.chinaemail.cn	18
833	mail.reed.jp	18
834	mail.casinocontroller.com	18
835	mailmx0001.rlp.de	18
836	mailmx0002.rlp.de	18
837	mx.junkemailfilter.com	18
838	mx.junkemailfilter.net	18
839	mx1.mailhop.org	18
840	mail-relay-1.nethost.cz	18
841	mx.beijing.gov.cn	18
842	mx2.belwue.de	18
843	mx3.belwue.de	18
844	mx4.belwue.de	18
845	smtp-relay.corpex-net.de	18
846	mx.hitcluster.com	18
847	mx2.mail.gov.mn	18
848	mx-mibc-fr-03.mailinblack.com	18
849	mx0.lcn.com	18
850	mx1.lcn.com	18
851	mx-mibc-fr-09.mailinblack.com	18
852	mx.dka.mailcore.net	18
853	mx0.mailinblack.com	18
854	mx.ilait.se	18
855	spamgw.blueweb.co.kr	18
856	mail.lottery.ltd.uk	18
857	selmx5.roscongress.org	18
858	mail.triptake.com	18
859	mxa.townsquaremedia.com	17
860	mx1.ex.360.cn	17
861	mx4.vevida.com	17
862	mx01.263xmail.com	17
863	mx1.arandomserver.com	17
864	mx2.arandomserver.com	17
865	mx1.redhat.com	17
866	mx1.de.opalstack.com	17
867	mx2.de.opalstack.com	17
868	us4-smtp-mx1.titanhq.com	17
869	us4-smtp-mx2.titanhq.com	17
870	mx4.funlife.cz	17
871	mx.inbound.elasticemail.com	17
872	mx1.intermax.nl	17
873	mx2.intermax.nl	17
874	mx01.logixmx.com	17
875	mx02.logixmx.com	17
876	mx1.greentube.com	17
877	mx2.greentube.com	17
878	mx.bpn.ge	17
879	mail.mbcore.io	17
880	mx10.jdm.pl	17
881	mx20.jdm.pl	17
882	fm.telconet.net	17
883	mx1.zoner.fi	17
884	mx2.zoner.fi	17
885	mx6.eganet.go.tz	17
886	mx1.secure.ly	17
887	mail.ratesolutions.eu	17
888	mailstream-australia-primary.area1.cloudflare.net	17
889	mailgw2.spd.co.il	17
890	mx.yourpaysitepartner.com	17
891	fimad.interieur.gouv.fr	17
892	reply.s10.exacttarget.com	17
893	mx1c51.megamailservers.eu	17
894	mxbackup2.svrsh.com	17
895	smtp1.egcloud.gov.eg	17
896	zmx33.zimbra.in.ua	17
897	mx.ct.mbox.net	17
898	mail2.casinocontroller.com	17
899	mailmx0003.rlp.de	17
900	mailmx0004.rlp.de	17
901	filter.premiumantispam.nl	17
902	fallback.premiumantispam.nl	17
903	mail.amamultimedia.com	17
904	dhl-com.fortimailcloud.com	17
905	mx.mail.gov.mn	17
906	backup.mail.profiwh.com	17
907	monday-relay.mxrouting.net	17
908	mail.dyson.cloud	17
909	mx3.eganet.go.tz	17
910	mail.advameg.com	17
911	mx-in1001.wikimedia.org	17
912	mx-in2001.wikimedia.org	17
913	dns10977.phdns5.es	17
914	mail.mojehobby.pl	17
915	mail6.finarea.ch	16
916	mx.latnet.lv	16
917	mx2.latnet.lv	16
918	forwarder.moddies.be	16
919	mxb.townsquaremedia.com	16
920	mailin2.mx.speedkom.net	16
921	mailin5.mx.speedkom.net	16
922	mx11-new.vatican.va	16
923	mx12-new.vatican.va	16
924	mx20.vatican.va	16
925	mx21.vatican.va	16
926	alt2.us.etp.fireeyegov.com	16
927	alt3.us.etp.fireeyegov.com	16
928	mx-wdc-1.ssnc-corp.cloud	16
929	mx1.dnsxperta.com	16
930	mail2.motorpresse.de	16
931	cx.spamfree.cz	16
932	dx.spamfree.cz	16
933	mx21.gmoserver.jp	16
934	securemail1.hostingservice.fi	16
935	mx-in02.natrohost.com	16
936	mx-in02b.natrohost.com	16
937	mx3.deem.sa	16
938	mx4.deem.sa	16
939	mail.cleanmail.eu	16
940	fallback1.server.eu	16
941	fallback2.server.eu	16
942	mx3.arandomserver.com	16
943	mx3.daouoffice.com	16
944	maila.dubai.gov.ae	16
945	mailb.dubai.gov.ae	16
946	mailc.dubai.gov.ae	16
947	mx1.landsh.de	16
948	mx2.landsh.de	16
949	mx.inet.vn	16
950	mx2.kpnqwest.it	16
951	mx.c1.icoremail.net	16
952	mx-in-hfd.apple.com	16
953	mx-in-vib.apple.com	16
954	mail1.employment.gov.au	16
955	mail2.employment.gov.au	16
956	mx-10.us-east.atmailcloud.com	16
957	email.wptechs.net	16
958	lobo.mercurio.cl	16
959	relay.ced.it	16
960	friday-relay.mxlogin.com	16
961	mx01.dandomain.dk	16
962	mx1.jimdo.com	16
963	mx2.jimdo.com	16
964	mx02.dioezesennetz.de	16
965	mx01.dioezesennetz.de	16
966	mx2.bitrixsoft.com	16
967	mail.tubecj.com	16
968	mailforward.iomart.com	16
969	mx2.sendcloud.org	16
970	bgmgate1.biglobe.ne.jp	16
971	bgmgate2.biglobe.ne.jp	16
972	mgy.cybermail.jp	16
973	mta.1stdomains.net.nz	16
974	fml01.sc-kanagawa.jp	16
975	mail.emb666.com	16
976	mail03.gov.cy	16
977	mx1.forwardmx.io	16
978	mx2.forwardmx.io	16
979	newsletter.cylex.de	16
980	spam.korea.kr	16
981	mx03.mvnet.de	16
982	mx04.mvnet.de	16
983	ksmg.mail.rwb.ru	16
984	mx1.gov.lk	16
985	mx2.freeola.com	16
986	mx3.freeola.com	16
987	mx4.freeola.com	16
988	mx5.freeola.com	16
989	rtmx2.roscongress.org	16
990	mail2.aliaweb.cz	16
991	antispam.explorerservizi.it	16
992	mail.myonlineradio.hu	16
993	mail02.fw.porsche.de	16
994	mail.fw.porsche.de	16
995	mx-ws.dca.untd.com	15
996	mx-ws.vgs.untd.com	15
997	mx1.r01.ru	15
998	smtp1.mafra.cz	15
999	smtp2.mafra.cz	15
1000	smtp3.mafra.cz	15

100 curiosities — singleton hostnames

Hostnames that appear exactly once in the Tranco top-1M (count == 1), sorted by length descending. These are the most bespoke / unusual setups — long custom names, region-specific hosters, one-off corporate gateways. Useful for qualitative research.

#	MX target (rare singleton)
1	port-arthur-historic-site-management-authority-mx1.firstcloudsecurity.net
2	port-arthur-historic-site-management-authority-mx2.firstcloudsecurity.net
3	cubic-transportation-systems-australia-mx1.firstcloudsecurity.net
4	cubic-transportation-systems-australia-mx2.firstcloudsecurity.net
5	mx.sendsimplepainting-com01e.mail.protection.outlook.comgrid.net
6	nlg-nhs-uk.mail.protection.outlook.com.disabled-dangler-101225
7	manak-waste-management-private-ltd-mx1.firstcloudsecurity.net
8	manak-waste-management-private-ltd-mx2.firstcloudsecurity.net
9	skeletal-triceratops-g8ku8ehowd09a0s8ppapxcdf.herokudns.com
10	p3plzcpnl502916.prod.phx3.secureserver.net.eco-reglalos.com
11	df-nu4a-g8rhv-jl689-g9c89-ruukm-t7dhr.in.tmes.trendmicro.eu
12	mx1.123-regmmailsec.protonmail.chailsec.protonmail.ch.co.uk
13	8ad2f72d-b2c4-4426-93fd-baacf7213b2d.in.tmes.trendmicro.eu
14	manulifesinochem-com02b.mail.protection.partner.outlook.cn
15	_dc-mx.fc2dea773184.medicalteaching.org.cdn.cloudflare.net
16	knowbe4-site-verification=34b9a58212e47bbcdf835890f6facdda
17	europeanchamber-com-cn.mail.protection.partner.outlook.cn
18	lb-sensproxy-2213375-dc68d533ade4.kr-gov.lb.naverncp.com
19	nfi34bdspmurbud57axm3w3xj2oyegddbnn6576ooea2jqnvu2mq.mx-
20	audifawnev-com-cn01bb.mail.protection.partner.outlook.cn
21	neusoftmedical-com01i.mail.protection.partner.outlook.cn
22	printondemand-worldwide.com.pri-mx.uk0101.smtproutes.com
23	canaancreative-com01e.mail.protection.partner.outlook.cn
24	u003d1a3b487390464833982a65fae59682b8.pamx1.hotmail.com
25	porschepreview-cn01i.mail.protection.partner.outlook.cn

Show rows 26 – 100

#	MX target (rare singleton)
26	etpr3nvk46n27vcc4juimkc7lxqosohb2zurr75mhylme5ye3awa.mx
27	sheltered-wildebeest-nw4f5n6yfgkz10hjq0e2b03r.herokudns
28	nospamcloudserver.germanywestcentral.cloudapp.azure.com
29	western-suburbs-leagues-club-mx2.firstcloudsecurity.net
30	leidseschouwburgstadsgehoorzaal-nl04b.c-v1.mx.microsoft
31	western-suburbs-leagues-club-mx1.firstcloudsecurity.net
32	porschedealercn-com.mail.protection.partner.outlook.cn
33	ipolaristech-com02b.mail.protection.partner.outlook.cn
34	8128664d7b9f7560c069c1bc8e6e2288e53721dc.msv1.invalid
35	3aca052794b229b9bc1b416f6993402b2b828e45.msv1.invalid
36	e57689ebf1cee2dcc74ca9695ba1a35f5249a903.msv1.invalid
37	5630e8ec42dcf18d9f086f6c16eb2667db34ace6.msv1.invalid
38	f59062e299f55da9447ced93e0ca43a2524e3386.msv1.invalid
39	mercedesbenz-cn02b.mail.protection.partner.outlook.cn
40	7312c3dbeed587e1ca48d18b0132c7c7d3d449d0.msv1.invalid
41	398fee270f77f506c1cc48e3a278690a231969e0.msv1.invalid
42	c37b41cc2aa83c50b8571a4fc41db855c664ecb8.msv1.invalid
43	638d21520d5d8632ca41f2350704980f00eee5ee.msv1.invalid
44	printondemand-worldwide.com.bak-mx.uk0101.smtpbak.com
45	90567ad2edb4ac9680d76a5d4492522415dc356e.msv1.invalid
46	86da5df266ee85ba1c9b2e19f890526f1191355e.msv1.invalid
47	b9b6ae914169a5a1688b1ae10978544884baaeb2.msv1.invalid
48	7544859033090d52a1be915fe96b1ec34f4dfd58.msv1.invalid
49	8a67419f6a694a1ec48efaa808ecca68e0bee47d.msv1.invalid
50	c7d3d7276f30dc72efbeb8e54423b1b47f63c58c.msv1.invalid
51	f00b1ca68dbdb60006726ab670cc3a4691003a6b.msv1.invalid
52	5975d01976fcb1ebf6eed8537fdc18fd513c4c74.msv1.invalid
53	8fca991f22bf0d3d9888adf9a9f177956ff29643.msv1.invalid
54	4b21ca12bd08ff22911a3537cf16967c602f815c.msv1.invalid
55	d3289eaaa594de2bf98e995630fdf76eb646bd67.msv1.invalid
56	0e52eafae7d1afa59efc92fe1a4ff3276f8eed08.msv1.invalid
57	b7d2174f2e1b3ef1065ffa8a05f24e3ca87487e4.msv1.invalid
58	abdf4c2da467191154ac33e376c4b147dc19c183.msv1.invalid
59	23a61b54849a99e548624c09d1cdddef7ffb2764.msv1.invalid
60	51e1151fac65ad93d2c3cb907f9a1e1bb5976586.msv1.invalid
61	e1373a12bca10839245327b9929bbbb41f14a8b3.msv1.invalid
62	dd65647d11fb1053fa50107650b42fc91a436e09.msv1.invalid
63	2a3139bde0fa73af719ed58cd4bc476dab5a81cc.msv1.invalid
64	8169f132d8bf45a25cc6548f6dcd7bd4bcfc39bb.msv1.invalid
65	b894a10f9d664f0b272df24349d0136fba05a89b.msv1.invalid
66	261fab891c9e30b9a8437b2307e7e67ebbfeee85.msv1.invalid
67	d8ef932105e6cdcd8d95d568e0ceb61e012b76b4.msv1.invalid
68	52f27914d6785f1569d999124b030c5d757f88dc.msv1.invalid
69	explorationpub-com.mail.protection.partner.outlook.cn
70	7d647202e4a762b842051e7ec60ff2fbd7fa2867.msv1.invalid
71	0fcc78af48b44f7236938cb34abbc42e37e614bf.msv1.invalid
72	9454fb2379b964a3496c91542921806588522fac.msv1.invalid
73	voipdnsservers-com.mail.protection.outlook.comook.com
74	7a1b696a13d31b9dd635db9c58d1f1c23c2c8288.msv1.invalid
75	6b2abbb43f243b33acbb3ee840a65711ba425d4b.msv1.invalid
76	279c75a743b1712505623de1926da99446f03967.msv1.invalid
77	eusmecentre-org-cn.mail.protection.partner.outlook.cn
78	gdsservices-com0i.mail.protection.partner.outlook.cn
79	5c7am4rrhs7xh7sgmu74qjaqd4phx2qifzbv6jl3i3xz3zhjqqqq
80	inbound.erasfellowshipdocuments.org.criticalpath.net
81	3osdx5cysr5ezqynjk3rxbwfxkoqwt47ek32cdcy7uar65mfindq
82	ceocoachinginternational-com.inbound.emailservice.io
83	porschepcn-com01i.mail.protection.partner.outlook.cn
84	f32ulet7jexwiwmrwipot2hs332uejyx5q5nwf3ggp77wer7utca
85	neueimpulseverlag-de01b1b.mail.protection.outlook.de
86	outdoormaster-com.mail.protection.partner.outlook.cn
87	\234\176\149\235\130\168\235\167\155\236\167\145.net
88	mfbwxutmypci.mail-manager-smtp.ap-southeast-2.on.aws
89	ceocoachinginternational-com.inbound.emailservice.cc
90	t2hbn3v62hu8w3s5.nx7lu0xvfrcp3ikg.pki-validation.com
91	3aas5bdlzoabws5g7mber6wtuyuvqjldemho2xwpx2pjf36yejoa
92	jqtyfzs58md1ra71.dbb7owi5iazdyuvq.pki-validation.com
93	chevrolet-com-cn.mail.protection.partner.outlook.cn
94	switchbot-com01e.mail.protection.partner.outlook.cn
95	healthkeepers-cn.mail.protection.partner.outlook.cn
96	baishancloud-com.mail.protection.partner.outlook.cn
97	digitalengineeringmagazin-de01i2i.v-v1.mx.microsoft
98	kennispleingehandicaptensector-nl.y-v1.mx.microsoft
99	decathlon-com-cn.mail.protection.partner.outlook.cn
100	xiaohongshu-net.mail.protection.partner.outlook.cn

TLD breakdown of Unknown bucket

Where the unmatched domains live, by registry suffix. Two-level TLDs like co.uk and com.br are recognised.

#	TLD	Domains in Unknown bucket
1	com	23 115
2	de	5 383
3	net	4 671
4	ru	3 516
5	org	2 824
6	pl	1 909
7	jp	1 545
8	it	1 494
9	nl	1 450
10	fr	1 444
11	cz	1 293
12	co.uk	1 039
13	com.br	882
14	eu	870
15	hu	739

Methodology in 30 seconds

Source: daily OpenINTEL Tranco snapshot (forward DNS, top-1M).
"Unknown / Generic": domains whose primary MX hostname does not match any entry in dictionaries/mx_providers.py (named providers) or generic mail.* / mx*.* patterns we attribute to "Generic / Self-hosted".
Self-hosted: the primary MX equals the apex domain or is a subdomain of it (example.com → mx.example.com).
Curiosities: hostnames with exactly one observation in the snapshot, sorted by length descending. Deterministic — same snapshot ⇒ same list.
Reproducibility: all CSVs are downloadable verbatim. No proprietary enrichment.

Generated automatically from OpenINTEL Tranco snapshot 2026-07-26. Aggregates only — raw data is deleted after analysis per the OpenINTEL data agreement.