How does the time-zone conversion work?

The calculator uses fixed UTC offsets. It converts the input hour to UTC by subtracting the from-offset, then adds the to-offset. The result wraps around a 24-hour clock, so a time like 23:00 in UTC+0 becomes 01:00 in UTC+2.

Does this calculator account for daylight saving time?

No. This tool uses fixed UTC offsets and does not adjust for daylight saving time (DST). If your region observes DST, check whether the standard or summer offset applies for your chosen date.

Time-Zone Meeting Planner

Pick an hour and two UTC offsets to instantly see what time a meeting in one city falls in another.

How UTC offset conversion works

Every time zone is defined by its offset from Coordinated Universal Time (UTC). To convert a time between two zones:

Subtract the from-offset to get the UTC equivalent.
Add the to-offset to get the local time in the target zone.
Wrap the result within 0–23 using modulo 24.

Formula: converted = ((hour - fromOffset + toOffset) % 24 + 24) % 24

The + 24 before the final modulo handles negative results (e.g. going west across midnight).

Worked example. 9:00 in New York (UTC−5) becomes 15:00 in London (UTC+1). UTC equivalent: 9 − (−5) = 14:00 UTC. London local: 14 + 1 = 15:00. Note: this uses fixed offsets and does not adjust for daylight saving.

A note on daylight saving

The UTC offset for most regions changes twice a year when clocks go forward or back. For example, New York is UTC−5 in winter (EST) but UTC−4 in summer (EDT). This calculator uses whichever fixed offset you select, so pick the correct one for the time of year.

Common UTC offsets for quick reference

City	Standard offset
Los Angeles	UTC−8
New York	UTC−5
London	UTC±0
Paris	UTC+1
Dubai	UTC+4
Singapore	UTC+8
Tokyo	UTC+9
Sydney	UTC+10