Timezone conversion
IST to GMT Converter (2026)
GMT (Greenwich Mean Time) is 5 hours and 30 minutes behind IST (India Standard Time). When it's 9:00 AM IST in Mumbai or New Delhi, it's 3:30 AM GMT in London. This table uses the fixed IST → GMT standard offset; live UK time is BST (UTC+1) from late March to late October, in which case London is 4h30m — not 5h30m — behind India.
Last updated June 25, 2026 · Maintained by Clockjumper
GMT is 5h30m behind IST. Subtract 5 hours 30 minutes from IST to get GMT. The best window for an India → UK live call is 1:30 – 5:30 PM IST (8:00 AM – 12:00 PM GMT) — the UK morning while the Indian workday is still open. From late March to late October the UK is on BST, so the gap narrows to 4h30m.
GMT is currently 4h30m behind IST.
Right now New Delhi / Mumbai (India) is on GMT+5:30 (UTC+5:30) and London (UK) on BST (UTC+1). This flips back to the standard IST/GMT gap once daylight saving ends.
Live clocks above use each region's current local time (DST-aware). The reference table below uses the fixed IST → GMT standard offset — see the DST section for how the gap changes across the year.
Interactive converter
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Key conversion times
- 9:00 AM IST3:30 AM GMTStart of the Indian workday — middle of the UK night
- 1:30 PM IST8:00 AM GMTEarly afternoon in India — start of the UK workday, prime overlap
- 3:30 PM IST10:00 AM GMTMid-afternoon in India — UK mid-morning, best call window
- 5:30 PM IST12:00 PM GMTEnd of the Indian workday — London noon
- 9:30 PM IST4:00 PM GMTIndian evening — UK afternoon, last live window
Full IST to GMT conversion table
| IST (Mumbai) | GMT (London) |
|---|---|
| 12:00 AM | 6:30 PM(previous day) |
| 1:00 AM | 7:30 PM(previous day) |
| 2:00 AM | 8:30 PM(previous day) |
| 3:00 AM | 9:30 PM(previous day) |
| 4:00 AM | 10:30 PM(previous day) |
| 5:00 AM | 11:30 PM(previous day) |
| 6:00 AM | 12:30 AM |
| 7:00 AM | 1:30 AM |
| 8:00 AM | 2:30 AM |
| 9:00 AM | 3:30 AM |
| 10:00 AM | 4:30 AM |
| 11:00 AM | 5:30 AM |
| 12:00 PM | 6:30 AM |
| 1:00 PM | 7:30 AM |
| 2:00 PM | 8:30 AM |
| 3:00 PM | 9:30 AM |
| 4:00 PM | 10:30 AM |
| 5:00 PM | 11:30 AM |
| 6:00 PM | 12:30 PM |
| 7:00 PM | 1:30 PM |
| 8:00 PM | 2:30 PM |
| 9:00 PM | 3:30 PM |
| 10:00 PM | 4:30 PM |
| 11:00 PM | 5:30 PM |
Daylight saving and how the gap changes
IST stays at UTC+5:30 year-round because India does not observe daylight saving. GMT is fixed UTC+0, but UK local time follows GMT only in winter — from the last Sunday of March to the last Sunday of October, London runs on BST (UTC+1). During BST the India ↔ London gap is 4h30m; the rest of the year it's the 5h30m shown in the table below.
Common mistake: abbreviation collision
This page uses "IST" as India Standard Time (Asia/Kolkata, UTC+5:30). Irish Standard Time (UTC+1) and Israel Standard Time (UTC+2) share the abbreviation but are entirely different zones.
Frequently asked questions
- What is the time difference between IST and GMT?
- IST (India Standard Time) is 5 hours and 30 minutes ahead of GMT (Greenwich Mean Time). To convert IST to GMT, subtract 5 hours 30 minutes.
- What time is 9 AM IST in GMT?
- 9:00 AM IST is 3:30 AM GMT the same day.
- What time is 5 PM IST in GMT?
- 5:00 PM IST is 11:30 AM GMT the same day.
- Does the UK stay on GMT all year?
- No. The UK observes British Summer Time (BST, UTC+1) from the last Sunday in March to the last Sunday in October. During those months, London is 4h30m behind India rather than 5h30m. GMT itself never changes — only UK civil time does.
- When is the best time to schedule an India → UK call?
- 1:30 – 5:30 PM IST (8:00 AM – 12:00 PM GMT) works for both sides. During BST, shift to about 12:30 – 4:30 PM IST so the UK end still lands in normal working hours.