Open5e vs TETR.IO

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

Uptime · 30d
Uptime · 90d—%—%
Uptime · 30d—%—%
P50 · ms
P95 · ms
Authnonenone
CORSyesyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseSRD content under OGL 1.0a; API/site MIT-licensedUnverified
Free tierFree, no API key requiredFree, no API key
Rate limitUnpublishedHonor server-provided cache expiry (~60s); docs require caching
In directory since2026-07-052026-07-05
operationalpartialdownno data

Open5e vs TETR.IO: common questions

Which is more reliable, Open5e or TETR.IO?

On our scheduled checks, TETR.IO leads on measured uptime — Open5e at —% versus TETR.IO at —% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.

Do Open5e and TETR.IO need an API key?

Neither needs a paid key — Open5e is callable with no signup, and TETR.IO is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Open5e and TETR.IO from the browser?

Yes — both Open5e and TETR.IO send CORS headers over HTTPS, so front-end code can fetch either directly with no backend proxy. That makes them easy to swap in a client-side app while you compare responses.

Are Open5e and TETR.IO free for commercial use?

Open5e has unclear commercial terms, and TETR.IO 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.