Compare GMT vs IST
See the current time difference between GMT and IST, check DST effects, and find the best hours for meetings across both time zones.
How to Find the Time Difference Between GMT and IST
Open the GMT vs IST converter: Go to https://www.xconvert.com/time-converter/gmt-vs-ist to load a comparison grid with GMT and IST already shown as separate rows on a 24-hour timeline. This view is useful when you are scheduling a call between London-based partners using Greenwich Mean Time and teams in India working on India Standard Time, especially for outsourcing, software development, customer support, and cross-border operations.
Add other relevant cities for context: Click + Add City and search for cities such as London, Mumbai, or Dubai to compare business overlap across finance, IT services, and trade routes. For example, London is often used as a practical reference for UK business hours, Mumbai is a major commercial center for India with a metropolitan population above 20 million, and Dubai helps companies coordinating shipments and regional sales between Europe, India, and the Gulf.
Drag to select a working window: Click Select to enable selection mode, then drag across the GMT row from 9:00 AM to 11:00 AM GMT; the purple highlight will show the matching time in IST as 2:30 PM to 4:30 PM IST on the same day. This makes it easy to confirm that a mid-morning meeting in GMT falls into India’s afternoon workday, which is often ideal for project reviews, legal discussions, and remote team handoffs.
Resize, move, and export the result: Drag the purple selection’s left or right handles to fine-tune the meeting window, or drag the center to shift the whole block later if you need to avoid lunch hours or evening calls in India. Once selected, use the export options — ICS download, Google Calendar, Gmail, Copy to clipboard, or Share link — to send the confirmed slot to clients, recruiters, offshore teams, or vendors so everyone sees the event in their own local time automatically.
GMT vs IST Offset Explained
GMT and IST are separated by an exact 5 hours 30 minutes, with IST ahead of GMT. That means when it is 9:00 AM GMT, it is 2:30 PM IST, and when it is 6:00 PM GMT, it is 11:30 PM IST. This half-hour difference is important because India does not align to a whole-hour offset, so teams scheduling meetings often need to account for the extra 30 minutes to avoid mistakes.
Greenwich Mean Time (GMT) is UTC+0:00, while India Standard Time (IST) is UTC+5:30 year-round. India does not observe daylight saving time, so IST remains fixed throughout the year. This makes India’s time stable for international operations, including software outsourcing, back-office processing, and support services for companies working with Europe, the Middle East, and Asia-Pacific.
The key seasonal issue is that GMT itself is only used in the UK during the winter period. In practice, the UK switches to British Summer Time (BST, UTC+1) on the last Sunday in March and returns to GMT on the last Sunday in October. For example, in 2025, the UK moves to BST on 30 March 2025 and returns to GMT on 26 October 2025, so during that BST period, the difference between UK local time and IST becomes 4 hours 30 minutes, not 5 hours 30 minutes.
This distinction matters for real scheduling. If you are comparing strict GMT vs IST, the difference is always +5:30 in India’s favor. But if you are actually planning a meeting with someone in London, the difference changes by season: a 10:00 AM London meeting in January is 3:30 PM in India, while a 10:00 AM London meeting in July is 2:30 PM in India because London is then on BST rather than GMT.
For business coordination, the overlap is usually strongest between GMT morning and IST afternoon. A common working overlap is roughly 8:00 AM to 12:00 PM GMT, which corresponds to 1:30 PM to 5:30 PM IST. That window is widely used by consulting firms, SaaS teams, financial services operations, and multinational companies running engineering, QA, analytics, or support functions from Indian cities such as Bengaluru, Hyderabad, Pune, Chennai, and Mumbai.
Frequently Asked Questions
What is the exact time difference between GMT and IST?
IST is exactly 5 hours 30 minutes ahead of GMT. If it is 12:00 noon GMT, it is 5:30 PM IST the same day. Because India uses a half-hour offset and does not change clocks seasonally, this exact GMT-to-IST difference stays constant.
Is IST always 5 hours 30 minutes ahead of GMT?
Yes, IST is always UTC+5:30, and GMT is always UTC+0:00, so the direct difference between those two standards is always 5 hours 30 minutes. Confusion usually happens when people say “GMT” but actually mean current UK local time, which becomes BST (UTC+1) during the summer months.
Does daylight saving time affect GMT and IST?
IST is not affected by daylight saving time because India does not observe DST at any point in the year. GMT itself also does not change, but places that use GMT in winter — especially the UK — switch to BST in summer, typically from the last Sunday in March to the last Sunday in October; in 2025, those dates are 30 March and 26 October.
When is the best time to schedule a meeting between GMT and IST?
The most practical meeting window is usually 8:00 AM to 11:00 AM GMT, which corresponds to 1:30 PM to 4:30 PM IST. That range fits standard office hours in India while still staying within the morning for GMT-based participants, making it useful for client calls, sprint reviews, interview loops, and vendor coordination.
If it is 9 AM GMT, what time is it in IST?
When it is 9:00 AM GMT, it is 2:30 PM IST on the same day. This is one of the most commonly used conversions for UK-India business communication because a morning start in GMT lands in the middle of the Indian workday, which is ideal for live collaboration.
Why do people get confused between GMT and London time when comparing with IST?
People often use “GMT” as shorthand for UK time, but London does not stay on GMT all year. In winter, London matches GMT (UTC+0), but in summer it uses BST (UTC+1), so the London-to-India gap changes from 5 hours 30 minutes in winter to 4 hours 30 minutes in summer.
Is GMT to IST a good overlap for remote teams?
Yes, GMT and IST usually provide a workable overlap, especially for companies with UK or West Europe leadership and engineering or support teams in India. A GMT morning maps to an IST afternoon, which is why this pairing is common in technology services, digital agencies, accounting operations, customer support centers, and multinational project delivery teams.