Amazon Route 53, Cloudflare and NearlyFreeSpeech
S&Ps use MarkMonitor.
S&Ps use MarkMonitor.
But for domain registrations alone it's fine.
(And since the records are size-limited, per-GB is roughly the same thing.)
"Except for Alias A/AAAA records mapped to AWS services listed below, you incur charges for every DNS query answered by the Route 53 service."