Sunrise-Sunset vs UK Carbon Intensity
Same instrument, two spec sheets — measured, not claimed.
Sunrise-Sunset vs UK Carbon Intensity: common questions
Which is more reliable, Sunrise-Sunset or UK Carbon Intensity?
On our scheduled checks, UK Carbon Intensity leads on measured uptime — Sunrise-Sunset at 99.02% versus UK Carbon Intensity at 100% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.
Which is faster, Sunrise-Sunset or UK Carbon Intensity?
Sunrise-Sunset has the lower median latency in our checks — Sunrise-Sunset responds in 204 ms versus UK Carbon Intensity at 789 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 Sunrise-Sunset and UK Carbon Intensity need an API key?
Neither needs a paid key — Sunrise-Sunset is callable with no signup, and UK Carbon Intensity is callable with no signup. Both are quick to prototype with; rate limits still apply.
Can I call Sunrise-Sunset and UK Carbon Intensity from the browser?
Yes — both Sunrise-Sunset and UK Carbon Intensity 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 Sunrise-Sunset and UK Carbon Intensity free for commercial use?
Sunrise-Sunset has unclear commercial terms, and UK Carbon Intensity allows commercial use on its free tier. 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.