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GMT to CST Time

Convert Greenwich Mean Time (GMT) to Central Standard Time (CST) efficiently to plan work meetings, online events, and appointments without any risk of timing errors or confusion.

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  • Runs in your browser
In short

CST (UTC−6) is 6 hours behind GMT (UTC+0) in standard time. 10:10 PM GMT is 4:10 PM CST. During daylight saving time (roughly March to early November) the gap is 5 hours, so 10:10 PM GMT is 5:10 PM CDT.

About GMT to CST Time

GMT covers Reykjavik and Accra, and the reference for every other zone. CST covers Chicago, Dallas, Houston, Mexico City and Winnipeg.

Working days overlap between 14:00 and 18:00 GMT, which is 09:00–13:00 in CST. That window is where calls land without anyone working late.

The clocks do not change on the same day, so a recurring meeting can shift by an hour in March and again in November. Check any standing call in the two weeks after each change.

How it works

Central Time (Chicago) is 6 hours behind of GMT / UTC between November and March, and 5 hours behind the rest of the year.

  1. Take the GMT time you want to convert.
  2. Subtract 6 hours between autumn and spring, or 5 hours during daylight saving.
  3. Roll the date forward or back if the result crosses midnight.

The gap changes because the two places start and end daylight saving on different dates — for a few weeks each spring and autumn the difference is an hour off its usual value. The converter above uses the live IANA time zone database, so it is right on those days too.

Zone details: GMT is +0 in winter and summer (UTC), CST is −6 in winter and −5 in summer.

Examples

A working day in GMT, seen from CST (during daylight saving):

GMT to CST at a glance
GMTCST
09:00 GMT04:00 CST
12:00 GMT07:00 CST
15:00 GMT10:00 CST
18:00 GMT13:00 CST
21:00 GMT16:00 CST

Meetings usually work best where the two working days overlap. Drag the timeline above to see the overlap for any hour, or use the full time zone converter for any other pair of cities.

GMT to CST Time: frequently asked questions

What is the time difference between GMT and CST?
CST is 6 hours behind GMT in standard time (GMT is UTC+0, CST is UTC−6). The gap can change by an hour for part of the year because GMT does not observe daylight saving and CST observes daylight saving (CDT).
What is 9 AM GMT in CST?
9:00 AM GMT is 3:00 AM CST (standard time).
Where is GMT used?
Greenwich Mean Time (always UTC+0; the UK switches to BST in summer) (UTC+0) is used in the the UK in winter, Iceland and parts of West Africa.
Where is CST used?
Central Standard Time (UTC−6) is used in US Central (Chicago, Dallas).