Golden hour and blue hour times

• Golden hour: the sun’s apparent altitude between −4° and +6°. Blue hour: between −6° and −4°. These are the photographic conventions this tool uses: other sites draw the lines slightly differently, so the boundaries are printed on every window.
• Altitude is apparent (refraction included), measured by scanning SunCalc’s own sun position and refining each crossing to the second. Civil twilight in the sunrise table uses the geometric −6° convention, so the two can differ by a few minutes, both are honest, they define different things.
• Windows the day cannot bound. Polar day, polar night, or a sun that never leaves a band all render as unbounded with a note, never as fake edges.

City list curated from GeoNames (geonames.org, cities500 database, CC BY 4.0), snapshot 2026-08-24, bounded to 151 major cities across six regions. Coordinates rounded to 2 decimals; ids are product slugs, not GeoNames ids.