Microsoft 365 (sender)

mailbox 🇺🇸 US

Microsoft 365 / Exchange Online outbound (spf.protection.outlook.com).

135,475SPF-authorising domains

21.748%of all SPF domains in Tranco top-1M

881distinct TLDs

2026-04-28snapshot date

TLD Distribution (top 30 of 881)

com — 57,870 (42.7%)

org — 8,562 (6.3%)

de — 6,555 (4.8%)

nl — 3,610 (2.7%)

co.uk — 3,499 (2.6%)

net — 3,249 (2.4%)

com.br — 2,463 (1.8%)

fr — 2,449 (1.8%)

it — 1,998 (1.5%)

com.au — 1,984 (1.5%)

ca — 1,731 (1.3%)

edu — 1,710 (1.3%)

es — 1,366 (1.0%)

se — 1,328 (1.0%)

be — 1,278 (0.9%)

co.jp — 1,179 (0.9%)

pl — 1,158 (0.9%)

ch — 1,073 (0.8%)

dk — 968 (0.7%)

cz — 949 (0.7%)

at — 927 (0.7%)

gov — 895 (0.7%)

eu — 892 (0.7%)

fi — 866 (0.6%)

no — 781 (0.6%)

org.uk — 732 (0.5%)

io — 719 (0.5%)

jp — 615 (0.5%)

cl — 606 (0.4%)

pt — 587 (0.4%)

Showing 100 of 135,475 domains. Sample sorted by length (shortest first).