IST to SGT time converter

How far apart are Kolkata and Singapore?

Singapore is 2 hours 30 minutes ahead of Kolkata all year, whether Kolkata is on IST and Singapore on SGT. Both cities change their clocks on the same dates, so the gap never moves for more than a few hours at a time — see below.

2026

2027

IST to SGT hour table

Every hour of a Kolkata day, read across to Singapore . A row marked +1 day is already tomorrow there; −1 day is still yesterday.

The clock names under each heading are the ones in force at either end of the year. For a half-hour time or a third city, use the timeline above: every clock moves to the instant you pick.

Working across Kolkata and Singapore

Singapore is two and a half hours ahead of India, and — unusually for the pairs on this site — that is the whole story. Neither country observes daylight saving: India has kept UTC+5:30 since independence and Singapore has kept UTC+8 since 1 January 1982, when it moved its clocks forward half an hour to match Malaysia. So the gap between Bengaluru and Singapore is the same number in January as in July, a standing meeting never drifts, and the hour table below has one column because there is only one answer.

The half hour on the Indian side is what makes the sum feel odd. Nine in the morning in Singapore is half past six in Kolkata; nine in the morning in Kolkata is half past eleven in Singapore. Everything on the Singapore side lands on the half hour from an Indian point of view and vice versa, which is a small nuisance in a calendar and a real one in a cron schedule — a job set for 09:00 Singapore time runs at 06:30 IST, which is before most Indian offices have anyone in them.

For an IT team split between the two, this is about as good as a cross-border pair gets. A nine-to-six day in India runs from 11:30am to 8:30pm in Singapore, so the two offices share every Indian working hour from 9am to 3:30pm — six and a half hours of overlap, more than most colleagues in the same country manage across a lunch break. The only friction is at the edges: Singapore's first two and a half hours have nobody awake in Indian offices yet, and India's last two and a half hours find Singapore already gone home.

Both abbreviations are clean by the standards of this page's neighbours. SGT means Singapore Time and nothing else in common use, and the same UTC+8 clock is shared by Kuala Lumpur, Manila, Perth, Hong Kong, Taipei and all of mainland China, so a Singapore time works unchanged for a colleague in Kuala Lumpur or Manila. IST is the ambiguous one — the same letters are Israel Standard Time and Irish Standard Time — but in a Singapore–India context nobody is confused. The tool above works in the IANA zone names Asia/Kolkata and Asia/Singapore regardless.

Because the difference is under three hours the date is the same in both cities for most of the day; only between 9:30pm and midnight in India is it already tomorrow in Singapore. A Singapore "midnight" deployment happens at 9:30pm in Bengaluru, which is late but not the next day. If what you have is a Unix timestamp, decode it in the epoch converter first — it has no time zone until you give it one.

Sources

The offsets, dates and hour tables above are computed when this page is built, from the time zone rules your browser itself ships. The rules come from:

• IANA Time Zone Database — the rules every browser ships
• ECMA-402 — the Intl.DateTimeFormat standard these figures are computed with