Chronicling America vs Free Dictionary API

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

Uptime · 30d
Uptime · 90d—%—%
Uptime · 30d—%—%
P50 · ms
P95 · ms
Authnonenone
CORSnoyes
HTTPSyesyes
Card requirednono
Commercial useyesunclear
Data licensePublic domain / no known copyright (Library of Congress)Unverified
Free tierFree — public-domain collection dataFree — limits not published
Rate limitLoC throttles heavy crawling (see LoC API policy)Unpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Chronicling America vs Free Dictionary API: common questions

Which is more reliable, Chronicling America or Free Dictionary API?

On our scheduled checks, Free Dictionary API leads on measured uptime — Chronicling America at —% versus Free Dictionary API 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 Chronicling America and Free Dictionary API need an API key?

Neither needs a paid key — Chronicling America is callable with no signup, and Free Dictionary API is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Chronicling America and Free Dictionary API from the browser?

Only Free Dictionary API 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 Free Dictionary API free for commercial use?

Chronicling America allows commercial use on its free tier, and Free Dictionary 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.