Time zone difference calculator
Convert a time between two UTC offsets, midnight rollover included.
Fill in the fields and the result will appear here automatically.
Converts a time between two zones given as UTC offsets. The offsets are entered as numbers, and that is a deliberate limitation: this calculator holds no time-zone database, does not infer daylight saving and keeps no history of past rules — it compares exactly the offsets you supply. Fractional offsets work: India at UTC+5:30 and Nepal at UTC+5:45 are current zones rather than curiosities, so the difference is computed in minutes. A rollover past midnight is shown on its own row, since otherwise the time would appear to be the same calendar day.
How it works
Formula and logic
Each offset first converts from decimal hours to whole minutes: 5.5 means 5 hours 30 minutes, not 5 hours 50 minutes. Offsets from−12 to+14 hours are accepted only when they specify exact whole minutes; fractional minutes are rejected. Destination offset minus source offset is added to the source clock in minutes. Day shift is the floor of total minutes/1440; the remainder gives the destination clock. Extreme offsets differ by 26 hours, so a shift of 2 days is possible. These are two entered fixed offsets without city selection, a calendar date, IANA rules or automatic daylight-saving inference.
Example
14:30 at UTC+3 corresponds to 06:30 on the same day at UTC−5.
Fields and units
- UTC offset — from — h. UTC offset in decimal hours: 5.5 = 5 h 30 min. It must equal whole minutes; city and daylight-saving rules are not selected automatically.
- UTC offset — to — h. UTC offset in decimal hours: 5.5 = 5 h 30 min. It must equal whole minutes; city and daylight-saving rules are not selected automatically.
- Hours — h. Whole numbers within the displayed range; invalid entries are not clamped to a boundary.
- Minutes — min. Whole numbers within the displayed range; invalid entries are not clamped to a boundary.
How to use
- — Enter the UTC offset of the zone where the time is known.
- — Enter the UTC offset of the zone you are converting to.
- — Enter the hours and minutes of the source time.
- — Check the calendar-day row: the time may have moved to an adjacent day.
Method and limitations
- Calculation method
- Formula and logic
- Data or methodology source
- IANA: offsets and daylight-saving rules vary by place and date; this calculation uses only entered fixed offsets
- Limitation
- These are two entered fixed offsets without city selection, a calendar date, IANA rules or automatic daylight-saving inference.
FAQ
Why are zones entered as numbers rather than picked from a list?
Because a list needs a time-zone database and yearly updates to it. Showing a stale rule is worse than asking for an offset you can verify right now.
Is daylight saving taken into account?
No. If one of the zones is on summer time, enter the offset that already includes it — UTC+2 instead of UTC+1, for example.
Are half-hour zones supported?
Yes. India uses UTC+5:30 and Nepal UTC+5:45; enter those as 5.5 and 5.75.
What does the day shift mean?
That the converted time landed on a neighbouring calendar day: plus one is the next day, minus one the previous.
How do I find a city's offset?
It is shown in the time-zone settings on your phone or computer next to the city name, usually as UTC+3 or GMT+3.