Chronicling America vs CustomGPT.ai

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

Uptime · 30d
Uptime · 90d0.0%0.0%
Uptime · 30d0.0%0.0%
P50 · ms
P95 · ms
AuthnoneapiKey
CORSnoyes
HTTPSyesyes
Card requirednono
Commercial useyesunclear
Data licensePublic domain / no known copyright (Library of Congress)Unverified
Free tierFree — public-domain collection dataFree tier — API key required
Rate limitLoC throttles heavy crawling (see LoC API policy)Unpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Chronicling America vs CustomGPT.ai: common questions

Which is more reliable, Chronicling America or CustomGPT.ai?

Both are neck-and-neck — Chronicling America and CustomGPT.ai each measure 0.0% 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.

Do Chronicling America and CustomGPT.ai need an API key?

Chronicling America needs no key, while CustomGPT.ai requires a free API key. If you want to start calling without signup, reach for Chronicling America first.

Can I call Chronicling America and CustomGPT.ai from the browser?

Only CustomGPT.ai is browser-friendly — it returns CORS headers over HTTPS. Chronicling America needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are Chronicling America and CustomGPT.ai free for commercial use?

Chronicling America allows commercial use on its free tier, and CustomGPT.ai 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.