Chess.com vs TETR.IO
Same instrument, two spec sheets — measured, not claimed.
Chess.com vs TETR.IO: common questions
Which is more reliable, Chess.com or TETR.IO?
On our scheduled checks, TETR.IO leads on measured uptime — Chess.com 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 Chess.com and TETR.IO need an API key?
Neither needs a paid key — Chess.com 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 Chess.com and TETR.IO from the browser?
Yes — both Chess.com 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 Chess.com and TETR.IO free for commercial use?
Chess.com 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.