Public Time API vs The SMS Works API

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

Uptime · 30d
Uptime · 90d100%100%
Uptime · 30d100%100%
P50 · ms242518
P95 · ms3821101
AuthnoneapiKey
CORSnoyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree tier — API key required
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Public Time API vs The SMS Works API: common questions

Which is more reliable, Public Time API or The SMS Works API?

Both are neck-and-neck — Public Time API and The SMS Works API each measure 100% uptime over 90 days on our probe schedule. Reliability here is verified from our own scheduled checks; use the 30-day bars above to see which has been steadier lately.

Which is faster, Public Time API or The SMS Works API?

Public Time API has the lower median latency in our checks — Public Time API responds in 242 ms versus The SMS Works API at 518 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 Public Time API and The SMS Works API need an API key?

Public Time API needs no key, while The SMS Works API requires a free API key. If you want to start calling without signup, reach for Public Time API first.

Can I call Public Time API and The SMS Works API from the browser?

Only The SMS Works API is browser-friendly — it returns CORS headers over HTTPS. Public Time API needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are Public Time API and The SMS Works API free for commercial use?

Public Time API has unclear commercial terms, and The SMS Works API 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.