GMT to CET

Enter a time in Greenwich Mean Time and read it in Central European Time. CET is usually 1 hour ahead of GMT.

Whether the gap holds all year

The gap holds at 1 hour ahead all year, because Greenwich Mean Time and Central European Time either change their clocks together or not at all — which makes this one of the few conversions you can safely memorise.

Which zones these letters mean

GMT resolves to Greenwich Mean Time and CET to Central European Time. Neither is ambiguous, so a time converted here means one thing only.

Questions

What does CST actually mean?

It depends who wrote it, and that is the problem. CST is US Central Time and it is also China Standard Time — fourteen hours apart. IST is India, Ireland and Israel. Every conversion page here names the zone it resolved an abbreviation to, rather than quietly picking one.

Why does the difference between two time zones change during the year?

Because countries change their clocks on different dates. The United States moves in March and November, the European Union in the last weekends of March and October, and the southern hemisphere moves the opposite way entirely. For a few weeks each year the usual gap is an hour out, which is when most mis-scheduled calls happen.