Kickbox vs The Calendar

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

Uptime · 30d
Uptime · 90d100%100%
Uptime · 30d100%100%
P50 · ms592588
P95 · ms36303550
Authnonenone
CORSyesyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified (US federal list per 5 U.S.C. § 6103)
Free tierFree — open disposable-address checkFree, no auth (per site)
Rate limitUnpublishedNone stated (site advertises no rate limit)
In directory since2026-07-052026-07-05
operationalpartialdownno data

Kickbox vs The Calendar: common questions

Which is more reliable, Kickbox or The Calendar?

Both are neck-and-neck — Kickbox and The Calendar 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, Kickbox or The Calendar?

The Calendar has the lower median latency in our checks — Kickbox responds in 592 ms versus The Calendar at 588 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 Kickbox and The Calendar need an API key?

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

Can I call Kickbox and The Calendar from the browser?

Yes — both Kickbox and The Calendar 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 Kickbox and The Calendar free for commercial use?

Kickbox has unclear commercial terms, and The Calendar 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.