Datamuse vs Energy-Charts API

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 licenseUnverifiedUnverified
Free tierFree — limits not publishedFree — limits not published
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Datamuse vs Energy-Charts API: common questions

Which is more reliable, Datamuse or Energy-Charts API?

On our scheduled checks, Energy-Charts API leads on measured uptime — Datamuse at —% versus Energy-Charts 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 Datamuse and Energy-Charts API need an API key?

Neither needs a paid key — Datamuse is callable with no signup, and Energy-Charts API is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Datamuse and Energy-Charts API from the browser?

Yes — both Datamuse and Energy-Charts API 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 Datamuse and Energy-Charts API free for commercial use?

Datamuse has unclear commercial terms, and Energy-Charts 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.