A time zone that is 45 minutes off

You send an invite. It comes back confirmed for 14:45, and you assume somebody mistyped it.

Nobody mistyped anything. Nepal is UTC+5:45, and 14:45 is exactly right.

The three of them

Nepal is the one that matters at scale. Chatham is the one that breaks software hardest, because it has a 45-minute offset and daylight saving, so it moves between two quarter-hour offsets.

Why Nepal chose it

Two reasons, both true.

Geographic: the standard is set to the meridian of Mount Gaurishankar, which genuinely corresponds to +5:45 and reflects the country's longitude better than +5:30 would.

Political: it is 15 minutes different from India. Nepal has never been colonised and is emphatic about not simply adopting its large neighbour's clock. The mountain provides the justification; the distinction provides the motive, and Nepalis will tell you so cheerfully.

What it breaks in practice

Meeting grids. Calendar software offering 15-minute increments handles it. Software offering 30-minute increments cannot express a Nepali working hour aligned to anything.

Mental arithmetic. "About six hours ahead" is 15 minutes wrong, which is exactly the size of error that makes someone late without making them suspicious.

Day boundaries. Midnight in Kathmandu is 18:15 UTC. Anything computing "start of day" across zones has a boundary aligning with nothing.

Overlap calculations. Shared-hours maths against Nepal must scan minute boundaries. Hour-level scanning is wrong at both ends of the window.

The good news for scheduling

Nepal does not observe daylight saving. UTC+5:45 is correct every day of the year, so once you have it right, it stays right — and any seasonal drift between you and Kathmandu comes entirely from your side.

That makes it easier to work with than India-plus-a-DST-observing-partner, once you stop rounding.

The engineering test

If you want to know whether a system's time handling is trustworthy, point it at Asia/Kathmandu.

A system that gets Nepal right — 45-minute offset, correct day boundaries, correct overlap windows, no rounding — is very likely correct everywhere else. A system that rounds Nepal to +6 is doing whole-hour arithmetic somewhere, which means it is also wrong for India, Iran, Myanmar, Newfoundland and parts of Australia.

Nepal is 30 million people and the single best test case in the database.

Related: Nepal is 45 minutes off · Half-hour and quarter-hour time zones

Figures on this page are computed from the IANA time zone database. Last generated 2026-08-18.