shipapis
StarSubmit an APISubmit API

Groundhog Day API vs National Grid ESO

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

APIGroundhog Day APIHEALTHY98National Grid ESOHEALTHY92
Uptime · 30d
Uptime · 90d100%100%
Uptime · 30d100%100%
P50 · ms262609
P95 · ms5961311
Authnonenone
CORSyesyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedNESO Open Data Licence (OGL-based); varies per dataset
Free tierFree — limits not publishedFree — limits not published
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Groundhog Day API vs National Grid ESO: common questions

Which is more reliable, Groundhog Day API or National Grid ESO?

Both are neck-and-neck — Groundhog Day API and National Grid ESO 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, Groundhog Day API or National Grid ESO?

Groundhog Day API has the lower median latency in our checks — Groundhog Day API responds in 262 ms versus National Grid ESO at 609 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 Groundhog Day API and National Grid ESO need an API key?

Neither needs a paid key — Groundhog Day API is callable with no signup, and National Grid ESO is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Groundhog Day API and National Grid ESO from the browser?

Yes — both Groundhog Day API and National Grid ESO 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 Groundhog Day API and National Grid ESO free for commercial use?

Groundhog Day API has unclear commercial terms, and National Grid ESO 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.