UTC Converter

Master Clock & Zone Grid

Common UTC Times

Switch to Set mode and jump to a frequently-converted UTC time.

UTC → City Conversion Table

Prefer the Greenwich hub view? Open the GMT Converter.

The UTC Conversion Formula

UTC vs GMT (and Zulu)

No saved times yet. Tap "Save This UTC Time" to remember up to six.

How to Use the UTC Converter

1. Leave the master clock in Live mode to watch the current UTC tick, or switch to Set mode to enter a specific UTC time.
2. Use the zone picker to toggle the cities you care about on or off; your selection is saved in your browser for next time.
3. Read each grid tile for that zone's offset and local time, with sun or moon shading showing day or night at a glance.
4. To convert a local time back to UTC, subtract the city's offset using the formula card, or use the Quick Conversion strip for UTC and EST.
5. Save the UTC time to history, and add one hour to any city currently on daylight saving before relying on the result.

Coordinated Universal Time, Explained

In 2026, a site-reliability engineer reading a stack of server logs, a satellite operator timing a pass, and a distributed team lead booking a sprint review all anchor on the same value: Coordinated Universal Time. The UTC Converter renders that anchor as a precise master clock paired with a grid of selectable zones, each tile showing its offset and local time for whatever UTC value you set. Where a hub dial is built for a quick radial read, this grid is built for the engineer who wants an exact, scannable table they can pin a dozen zones to.

Coordinated Universal Time is the primary time standard by which the world regulates clocks. It is computed from International Atomic Time (TAI), kept by some 400 atomic clocks worldwide and coordinated by the International Bureau of Weights and Measures (BIPM), then adjusted with occasional leap seconds so it never drifts more than 0.9 seconds from UT1, the time defined by the Earth's actual rotation. UTC replaced Greenwich Mean Time as the world's civil reference in 1972, and every modern operating system, database, and network protocol stores time as a UTC offset.

The UTC versus GMT nuance trips up almost everyone, so it is worth stating plainly: GMT (Greenwich Mean Time) is a time zone tied to the mean solar time at the Royal Observatory in Greenwich, while UTC is an atomic time standard, not a time zone. They share the same zero offset and rarely differ by more than a fraction of a second, so in everyday use 12:00 UTC and 12:00 GMT are the same wall time. The difference matters to astronomers and metrologists, who care about leap seconds and the Earth's slowing spin, far more than to someone booking a call.

The zone offsets come from the IANA Time Zone Database (the tz database, zoneinfo, or Olson database after founder Arthur David Olson), the canonical dataset used by Linux, macOS, Java, Python, and the browser's own Intl.DateTimeFormat API. Each grid tile is keyed by an Area/Location identifier such as America/New_York, Asia/Kolkata, and Pacific/Auckland. Because the converter and your operating system read the same database, a UTC time set here produces the exact local times your calendar would show.

The grid deliberately includes the awkward fractional offsets that whole-hour tools mangle. India Standard Time is UTC+5:30, standardised in 1906 around the 82.5 degrees east meridian; Nepal is UTC+5:45, the only quarter-to-the-hour national offset, set to centre on Mount Everest's longitude; and the Chatham Islands run UTC+12:45. Selecting Mumbai and Kathmandu side by side at 12:00 UTC shows 5:30 PM and 5:45 PM respectively, fifteen minutes apart, which is exactly the kind of edge case the grid makes legible.

Engineers lean on UTC precisely because it removes ambiguity. Server logs, distributed-database timestamps, Git commits, TLS certificate validity windows, and GPS time all reference UTC or a fixed offset from it, so that an event at 14:32:07 UTC means the same instant whether it was recorded in Frankfurt or Sao Paulo. The practice of storing UTC and converting only for display, using a tz-aware formatter, is the standard recommended by virtually every backend style guide, because local times are ambiguous across daylight-saving transitions while UTC never is.

Daylight Saving Time is the one thing the offsets here intentionally hold constant. The grid shows standard-time offsets, so during summer time a city shifts an hour: the United States moves on the second Sunday of March and first Sunday of November under the Energy Policy Act of 2005, the European Union on the last Sundays of March and October under EU Directive 2000/84/EC, while India, Japan, and most equatorial regions never change. UTC itself never shifts — that fixedness is the whole point — so to read a city currently on daylight saving, add one hour to its grid tile and confirm against a live, tz-aware calendar before relying on the result.