Catalogue of SPF-side senders authorised to send mail on behalf of domains in the Tranco top-1M: marketing ESPs, SaaS apps, security gateways and forwarders. Click a card for the homepage; mini-charts show share dynamics over past snapshots.
Source: OpenINTEL forward-DNS Tranco snapshot (2026-05-04).
Sender patterns: dictionaries/esps.py + dictionaries/saas_senders.py.
Descriptions: dictionaries/saas_meta.py.
Sparklines render only for senders tracked in history.json; new
senders will start appearing as future scans accumulate.