⚠️ Caution: This is an early demo of our test updates for NCSC's 2025 TLS guidelines, to allow you to test against the new guidelines. Some explanation text is still missing, out of date, or in rough draft state. Test evaluations may still change. This URL is an active development environment and has limited availability - it may be down for hours or days.

Protection against email phishing (DMARC, DKIM and SPF)

Why

Usage statistics

Background information

Specifications