shipapis
StarSubmit an APISubmit API

mail.tm vs PostStack

Same instrument, two spec sheets — measured, not claimed.

APImail.tmHEALTHY82PostStackHEALTHY87
Uptime · 30d
Uptime · 90d84.3%100%
Uptime · 30d75.0%100%
P50 · ms7091066
P95 · ms23511890
AuthnoneapiKey
CORSnono
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — temporary mailboxesFree tier — key may be required
Rate limitRate limited (429 on exceed); exact policy per docs.mail.tmUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

mail.tm vs PostStack: common questions

Which is more reliable, mail.tm or PostStack?

On our scheduled checks, PostStack leads on measured uptime — mail.tm at 84.3% versus PostStack at 100% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.

Which is faster, mail.tm or PostStack?

mail.tm has the lower median latency in our checks — mail.tm responds in 709 ms versus PostStack at 1066 ms (P50). Tail latency (P95) is in the table above; for most workloads the median is the number that shapes how the API feels.

Do mail.tm and PostStack need an API key?

mail.tm needs no key, while PostStack requires a free API key. If you want to start calling without signup, reach for mail.tm first.

Can I call mail.tm and PostStack from the browser?

Neither sends browser-friendly CORS headers reliably, so call mail.tm and PostStack from a server or proxy rather than client-side. The CORS and HTTPS rows above show exactly what we detected for each.

Are mail.tm and PostStack free for commercial use?

mail.tm has unclear commercial terms, and PostStack has unclear commercial terms. We track service terms and the data license as separate fields — see the Commercial use and Data license rows above, and confirm both before shipping either in a paid product.