5 PM IST to EST

Split-Flap Departure Board

Common India Times

One-click presets for the most-searched India meeting and handoff slots.

IST → EST Hour-by-Hour Table

Need the reverse? Go from EST to IST instead.

The Offset Formula

Zone Reference

Offsets per the IANA tz database. India anchored to 82.5° E meridian; US DST per the Energy Policy Act 2005.

No saved conversions yet. Tap "Save to History" to remember up to six IST → EST lookups.

How to Convert IST to EST on the Split-Flap Board

1. Set the India time — type it into the IST time field or tap a preset chip for a common handoff slot.
2. Pick the Eastern mode: EST (UTC-5) for November–March or EDT (UTC-4) for March–November per the Energy Policy Act 2005 schedule.
3. Watch the bottom row of the split-flap board flip to the New York time, including a "prev day" flag when the conversion rolls back past midnight.
4. Read the offset ladder beside the board to see the exact gap — −10h 30m on EST or −9h 30m on EDT.
5. Check the verdict band, then save the snapshot to compare handoff windows across the week.

Why This Converter Exists

In 2026, a delivery lead in Hyderabad needs to know exactly when a 5 PM IST end-of-day handoff lands in New York before promising a same-day reply. The recurring friction — what time is 5 PM IST in EST, and is anyone in the office on the US East Coast — is precisely what this split-flap departure board answers. India Standard Time (IST) is locked at UTC+5:30 and observes no daylight saving, so the only moving part is whether the United States East Coast is currently on Eastern Standard Time (EST, UTC-5) or Eastern Daylight Time (EDT, UTC-4).

India Standard Time was standardised in 1906, anchored to the 82.5° E meridian that passes through Mirzapur near Allahabad. The famous half-hour offset — the :30 that trips up newcomers — was a single national compromise between the older Bombay Time and Calcutta Time used under the British Raj. Because the offset is +5:30 rather than a whole number of hours, every IST-to-EST conversion lands on a half-hour: 5:00 PM IST becomes 6:30 AM EST in winter and 7:30 AM EDT in summer.

US Eastern Time, by contrast, swings twice a year. Under the US Energy Policy Act of 2005, daylight saving in the United States begins on the second Sunday of March and ends on the first Sunday of November. From March to November New York runs on EDT (UTC-4); the rest of the year it runs on EST (UTC-5). That single hour is why 5 PM IST to EST is 6:30 AM in winter but 7:30 AM in summer — the IST clock never moves, so the whole shift comes from the Eastern side.

The IANA time zone database (the tz database maintained by Paul Eggert and contributors) encodes Eastern Time as America/New_York and India as Asia/Kolkata. Asia/Kolkata has carried a flat +05:30 rule since 1945 with no daylight-saving transitions, which is why software never special-cases India for DST. America/New_York carries the full US DST ruleset, so a correct converter must know the date — or let you toggle EST/EDT manually, exactly as the split-flap board here does.

GMT and UTC are often swapped in calendar invites, but they are not identical: GMT is a time zone (UTC+0, the Greenwich meridian), while UTC is the atomic time standard the world's clocks are disciplined to. IST is UTC+5:30 and Eastern Time is referenced to UTC as well, so the cleanest mental model is to convert through UTC: IST is UTC plus 5:30, EST is UTC minus 5, so the gap is a fixed 10 hours 30 minutes in winter and 9 hours 30 minutes in summer.

The practical reason this page exists is the handoff-window problem. A 5 PM India close-of-business lands at 6:30–7:30 AM in New York — the very start of the US East Coast day. That makes it the single best moment for an India-to-US async handoff: India wraps up and the US picks up almost immediately. Shift the India clock earlier and New York is still asleep; shift it later and you push into the US morning meetings. The split-flap board lets you flip to any India hour and instantly read the Eastern result, with a verdict band scoring how civilised that US time really is.

Distributed teams have leaned on this exact conversion since the offshore-IT boom of the late 1990s, when firms like Infosys, Wipro, and TCS built delivery centres aligned to US East Coast clients in New York, Boston, and Atlanta. The IST-evening to EST-morning overlap is the classic follow-the-sun pattern: India closes the day, the US opens it, and the work never sleeps. This tool turns that institutional rhythm into a flippable, shareable answer for any hour.