Golden & Blue Hour
Twilight, golden hour and blue hour windows from latitude and date
Sun altitudes from astronomy-engine. Offline city catalog. Times formatted in the chosen IANA zone.
About this tool
List sunrise, sunset, civil/nautical/astronomical twilight and golden or blue hour windows. Offline, no API. Golden & Blue Hour runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.
What this tool does not do
- Golden & Blue Hour is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.
How do I use this tool?
How do I use Golden & Blue Hour?
Open Golden & Blue Hour, enter or paste your input, and copy the result. The page works without an account.
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