What the match percentage means
A match means the complete returned record set equals your expected set, or the most common set if no expected value is supplied. Failed requests are excluded from the denominator and listed separately. This is a comparison of six resolvers, not proof of global completion.
TTL is an estimate, not a deadline
The largest remaining TTL among differing answers estimates how long the observed caches may keep them. Negative caching, stale-answer policies and authoritative-server changes can extend what users see. A zero TTL is not a guarantee of immediate propagation.
Expected values and record sets
Enter each MX record with its numeric priority and host on the same line. TXT values retain case and internal spaces. IPv6 notation is normalized, duplicate records are removed and ordering does not affect equality.
Why Google ECS is separate
ECS adds a client-subnet hint to a Google query; it is not a request from that country’s ISP. A returned scope of /0 reports no regional distinction. Counting repeated Google queries as independent locations would distort agreement, so diagnostics are excluded from the percentage.
Bounded monitoring
Repeat checks are opt-in and are never enabled by a shared URL. Monitoring stops at 100% agreement, 60 rounds, 30 minutes or when the tab becomes hidden. History remains in memory and disappears on reload.