Step 01
Think in UTC offsets, not just city names.
A UTC offset is the difference between local time and Coordinated Universal Time. London is normally UTC+0, but UTC+1 during British Summer Time. New York is usually UTC−5, but UTC−4 during daylight saving.
City names are only a shortcut. The offset that applies on the date matters because daylight-saving schedules change twice a year.
Step 02
Understand the conversion.
The converter uses the fixed offsets you select and clearly labels the result. It does not guess daylight-saving changes, so choose the offset that applies on the date.
- Normalise the entered local time to UTC by subtracting the source offset.
- Add the target offset to obtain the converted local time.
- Difference = target offset − source offset.
- Always record the date as well as the time; crossing midnight changes the day.
Step 03
Worked example: 12:00 UTC to a UTC+1 meeting.
12:00 at UTC+0 becomes 13:00 at UTC+1, with a difference of +1 hour. If the same moment is shown to someone in New York during summer (UTC−4), their local time is 08:00.
The same city pair can produce a different result in winter because one or both locations may change offset. Recheck the date before every meeting.
Step 04
Handle daylight saving explicitly.
A fixed-offset converter is intentionally transparent: you choose the offsets, so the result is only as correct as those choices.
- Find the offset that applies on the meeting date for each location.
- Remember that change dates differ between regions.
- Do not assume UTC+1 means the same thing year-round for every place.
- Recheck shortly before the meeting because DST schedules can change.
Step 05
Confirm with the people involved.
Use the worksheet to record the event, date, source and target offsets, converted time and who should confirm. Send the UTC instant as well as a local time when practical, because UTC does not change with daylight saving.
This guide is general planning help, not a scheduling guarantee.
Free reusable resource
Keep a practical worksheet.
Download a blank, editable file and keep the plan with your own records. No email address is required.
Time-zone conversion worksheet
Record each event, its date and time, source and target offsets, converted time and the participants who must confirm.
Sources and further guidance
References used for this guide.
Time Zone Database
IANA. The canonical source for time-zone and daylight-saving rules used by operating systems and applications.