Convert a time between cities, then switch to the planner when you need a slot that works for everyone.
How do you convert a time between two time zones?
Pick the city the time is in, set the date and the clock time, then pick the cities you want it in. The date matters because daylight saving changes the offset. 9:00 PM in Kuala Lumpur on 1 July is 2:00 PM in London, the same day.
Your converted times will appear here after you press Convert.
How time zone conversion works
A local time plus a time zone identifies one exact moment. That moment is then described using each other zone's rules for the same date. Calcadian uses IANA zone identifiers such as Asia/Kuala_Lumpur and America/New_York, which carry the full history of offset and daylight-saving rules.
Why the date matters
Many zones change their offset twice a year. New York is UTC-5 in winter and UTC-4 in summer. London is UTC+0 and UTC+1. Sydney moves the other way, because its summer is in December. Converting without a date is a guess, so the date field is required.
UTC offsets and time zones are not the same thing
UTC+1 is an offset, a single number. Europe/London is a zone, a set of rules that says which offset applies on which date. Sharing a converted time with the date attached keeps it reproducible, which is why the share link includes the date.
Half-hour and 45-minute time zones
Not every zone sits on a whole hour. India runs at UTC+5:30, Adelaide at UTC+9:30 in winter, Nepal at UTC+5:45 and the Chatham Islands at UTC+12:45. These are handled the same way as any other zone.
Planning meetings across time zones
Set each person's working hours in their own local time, choose a length, and the planner shows the start times where everyone is inside those hours. Where there is no overlap it says so rather than suggesting a slot someone would have to take at 3am.
Worked example
1 July, 9:00 PM in Kuala Lumpur is 2:00 PM in London at UTC+1 on the same day, 9:00 AM in New York at UTC-4 on the same day, and 10:00 PM in Tokyo at UTC+9.
Every zone has an offset from UTC. The source time is turned into a single moment in time, then that moment is shown using each destination zone's offset for that exact date.
Why does the date matter?
Offsets change during the year in zones that use daylight saving. London is UTC+0 in January and UTC+1 in July, so converting without a date gives the wrong answer for half the year.
Do you support half-hour and 45-minute zones?
Yes. India runs at UTC+5:30, Adelaide at UTC+9:30 or UTC+10:30, Nepal at UTC+5:45 and the Chatham Islands at UTC+12:45 or UTC+13:45. Offsets are read from the calendar rules, not rounded to whole hours.
What if the time I enter does not exist?
On the day clocks spring forward, an hour of local time is skipped. If you enter a time inside that gap, the converter says so instead of quietly moving your time.
How does the meeting planner decide on a time?
It compares the working hours you set for each participant and shows where they overlap. It is your rules, not a recommendation, so you can widen the hours and see more options.
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Calcadian calculators are for general planning and informational use. Please verify critical deadlines, legal, payroll, tax, HR, or official requirements with the relevant authorities or a qualified professional.
