About This Tool
Timezones are regions on Earth that use the same standard time. They are based on the Earth's rotation and are typically offset from UTC (Coordinated Universal Time). This tool uses IANA timezone data and your browser's Intl API, so times are accurate and automatically account for daylight saving time.
How to Use
Search Timezones: Type a city or region to filter the list
View Time: Select a timezone to see its current time, UTC offset, sunrise/sunset and clock display
Watch Day/Night: The map shows the real-time day/night cycle (with seasonal tilt) based on UTC
Compare Zones: Star zones in the list to pin them to the comparison panel, then drag the time-shift slider to preview any future or past moment across all pinned zones
Frequently Asked Questions
Are the times DST-accurate?
Yes. Times are computed via the browser Intl API using IANA timezone data, so daylight saving transitions are applied automatically.
Why are timezones 1 hour apart?
The Earth rotates 360° in 24 hours, so each hour corresponds to 15° of longitude — though some regions use 30- or 45-minute offsets.
How is the day/night cycle calculated?
The sun position uses current UTC for longitude and the solar declination (±23.45° across the year, via Cooper's equation) for latitude, so you see both the east-west rotation and the seasonal day/night tilt.
How accurate are the sunrise and sunset times?
Sunrise and sunset are computed from latitude and day-of-year using the standard solar equations. Equation-of-time and atmospheric refraction are ignored, so values are typically within a few minutes of published times.
How does the compare view work?
Click the star next to any timezone to pin it. Pinned zones appear in the comparison strip at the bottom. Drag the slider to shift time by up to ±12 hours and instantly see the equivalent moment in every pinned zone — great for scheduling meetings across the globe.
Which timezone is shown by default?
Your browser's detected timezone is selected on load, falling back to UTC if it's not in our list.