Karachi is 4 hours ahead of London for most of the year: when it is 10:00 am in London it is 2:00 pm in Karachi. In offset terms London is on UTC+00:00 and Karachi is on UTC+05:00 in January, and UTC+01:00 and UTC+05:00 in July. The converter above works from your browser’s own time zone data, so the figure it shows is the one in force today rather than the one that was in force when this page was written.
The difference is not constant, because only one of the two cities observes daylight saving. In 2026, London changes on 29 March and 25 October and Karachi does not change at all. That leaves 3 distinct periods in the year, and the table below gives the exact dates. It is the short windows that catch people out: a recurring call booked in one city’s clock silently moves in the other’s.
For arranging anything, the number that matters is the overlap. London works 09:00 to 17:30 and Karachi works 09:00 to 17:00, which leaves 09:00 to 13:00 in London — 13:00 to 17:00 in Karachi — as the window when both are open. That is 4 hours of shared working time. Both cities work Monday to Friday, so only the clock has to be reconciled.
Two local details worth knowing. The City works 09:00 to 17:30, and the 08:00 market open means email is answered well before the official start. Pakistan keeps UTC+05:00 all year, half an hour behind India, which is the usual source of confusion on regional calls.
Write the invitation in both clocks. "10:00 London / 14:00 Karachi" removes the ambiguity that abbreviations introduce — London alone is read as GMT in winter and BST in summer, and calendar software will happily convert one into the other without telling you.
The formula
local London- The time you enter, on the London clock
offset- Each city’s UTC offset at that moment, read live from the IANA time zone database in your browser
+4- The difference in hours that holds for most of 2026: Karachi is 4 hours ahead of London
day shift- Whether the converted time falls on the previous, same or next calendar day in Karachi
How it works, step by step
- Enter a time in London using the 24-hour hour box and the minute box — 15:30 is hour 15, minute 30.
- Your browser reports the UTC offset in force in London and in Karachi for that moment, so a date near a daylight saving transition is handled correctly rather than with a fixed 4 hour rule.
- The second offset minus the first gives the difference, which is added to the time you entered. A result past midnight is marked as the next or previous day, because that is where most conversion mistakes live.
- The panel also shows the current time in both cities, the date in Karachi, and whether the two offices are open at the same moment.
Worked examples
09:00 in London
09:00 in London is 13:00 in Karachi — inside Karachi office hours. In 12-hour terms, 9:00 am against 1:00 pm. Both offices are open at that moment, so it is a slot either side can accept.
12:00 in London
12:00 in London is 16:00 in Karachi — inside Karachi office hours. In 12-hour terms, 12:00 pm against 4:00 pm. Both offices are open at that moment, so it is a slot either side can accept.
16:30 in London
16:30 in London is 20:30 in Karachi — after the Karachi working day has finished. In 12-hour terms, 4:30 pm against 8:30 pm. Only one of the two offices is open at that moment, so it is worth offering rather than assuming.
The 1 January window, when the usual answer is wrong
Between 1 January and 28 March the difference is +05:00 rather than +04:00, because one city has changed its clocks and the other has not. In that window 10:00 in London is 15:00 in Karachi, an hour away from where a fixed-offset table would put it.
How to read your score
Frequently asked questions
How many hours ahead of London is Karachi?
Karachi is 4 hours ahead of London for most of 2026, so 09:00 in London is 13:00 in Karachi. The difference changes during the daylight saving changeovers, and the table on this page lists every period in the year with its exact dates.
What is 2 pm London time in Karachi?
6:00 pm, after the Karachi working day has finished. In 24-hour form 14:00 in London is 18:00 in Karachi, and that is outside working hours in Karachi.
What is the best time to call between London and Karachi?
Anywhere between 09:00 and 13:00 London time, which is 13:00 to 17:00 in Karachi. Both offices are open across that whole window — 4 hours of it. If you want one answer rather than a range, 11:00 in London is the middle of the overlap.
Is Karachi ahead of or behind London?
Karachi is ahead. London is at UTC+00:00 and Karachi is at UTC+05:00 in mid-January, and UTC+01:00 and UTC+05:00 in mid-July. The clock moves forward going from London to Karachi, which is why Karachi reaches the end of its working day first.
Do London and Karachi change their clocks on the same date?
No. In 2026, London changes on 29 March 2026 and 25 October 2026, and Karachi does not change its clocks at all. That is why the difference between them takes 2 different values across the year rather than one.
What do the abbreviations for London mean?
London is on GMT in winter and BST in summer, while Karachi uses PKT and PKT. Abbreviations are the least reliable way to write a time: several are ambiguous between regions, and the summer and winter forms are an hour apart. A UTC offset, or the time given in both cities, cannot be misread.
Does this converter stay correct after the clocks change?
Yes. It does not use a stored number for the difference. Each time you change a value it asks your browser for the UTC offset that Europe/London and Asia/Karachi are on at that moment, using the IANA time zone database that ships with your operating system, and takes the difference. The tables on this page are computed from the same database for 2026.
London to Karachi: every hour, every period of 2026, and meeting slots
| London (24h) | London (12h) | Karachi (24h) | Karachi (12h) | Status |
|---|---|---|---|---|
| 00:00 | 12:00 am | 04:00 | 4:00 am | outside office hours |
| 01:00 | 1:00 am | 05:00 | 5:00 am | outside office hours |
| 02:00 | 2:00 am | 06:00 | 6:00 am | outside office hours |
| 03:00 | 3:00 am | 07:00 | 7:00 am | outside office hours |
| 04:00 | 4:00 am | 08:00 | 8:00 am | outside office hours |
| 05:00 | 5:00 am | 09:00 | 9:00 am | office hours in Karachi |
| 06:00 | 6:00 am | 10:00 | 10:00 am | office hours in Karachi |
| 07:00 | 7:00 am | 11:00 | 11:00 am | office hours in Karachi |
| 08:00 | 8:00 am | 12:00 | 12:00 pm | office hours in Karachi |
| 09:00 | 9:00 am | 13:00 | 1:00 pm | office hours in both |
| 10:00 | 10:00 am | 14:00 | 2:00 pm | office hours in both |
| 11:00 | 11:00 am | 15:00 | 3:00 pm | office hours in both |
| 12:00 | 12:00 pm | 16:00 | 4:00 pm | office hours in both |
| 13:00 | 1:00 pm | 17:00 | 5:00 pm | office hours in London |
| 14:00 | 2:00 pm | 18:00 | 6:00 pm | office hours in London |
| 15:00 | 3:00 pm | 19:00 | 7:00 pm | office hours in London |
| 16:00 | 4:00 pm | 20:00 | 8:00 pm | office hours in London |
| 17:00 | 5:00 pm | 21:00 | 9:00 pm | office hours in London |
| 18:00 | 6:00 pm | 22:00 | 10:00 pm | outside office hours |
| 19:00 | 7:00 pm | 23:00 | 11:00 pm | outside office hours |
| 20:00 | 8:00 pm | 00:00 (next day) | 12:00 am (next day) | outside office hours |
| 21:00 | 9:00 pm | 01:00 (next day) | 1:00 am (next day) | outside office hours |
| 22:00 | 10:00 pm | 02:00 (next day) | 2:00 am (next day) | outside office hours |
| 23:00 | 11:00 pm | 03:00 (next day) | 3:00 am (next day) | outside office hours |
Computed at a difference of 4 hours, which is the one that holds for most of 2026. During the transition windows in the table below, shift the right-hand columns by an hour.
| Period | Length | London offset | Karachi offset | Difference | Abbreviations |
|---|---|---|---|---|---|
| 01 Jan to 28 Mar | 87 days | UTC+00:00 | UTC+05:00 | +5:00 | GMT / PKT |
| 29 Mar to 24 Oct | 210 days | UTC+01:00 | UTC+05:00 | +4:00 | BST / PKT |
| 25 Oct to 31 Dec | 68 days | UTC+00:00 | UTC+05:00 | +5:00 | GMT / PKT |
Every row is read from the IANA time zone database. Short periods appear where one city has changed its clocks and the other has not yet done so.
| London | 12-hour | Karachi | Verdict |
|---|---|---|---|
| 06:00 | 6:00 am | 10:00 | Too early in London |
| 06:30 | 6:30 am | 10:30 | Too early in London |
| 07:00 | 7:00 am | 11:00 | Too early in London |
| 07:30 | 7:30 am | 11:30 | Too early in London |
| 08:00 | 8:00 am | 12:00 | Too early in London |
| 08:30 | 8:30 am | 12:30 | Too early in London |
| 09:00 | 9:00 am | 13:00 | Good — both offices open |
| 09:30 | 9:30 am | 13:30 | Good — both offices open |
| 10:00 | 10:00 am | 14:00 | Good — both offices open |
| 10:30 | 10:30 am | 14:30 | Good — both offices open |
| 11:00 | 11:00 am | 15:00 | Good — both offices open |
| 11:30 | 11:30 am | 15:30 | Good — both offices open |
| 12:00 | 12:00 pm | 16:00 | Good — both offices open |
| 12:30 | 12:30 pm | 16:30 | Good — both offices open |
| 13:00 | 1:00 pm | 17:00 | After hours in Karachi |
| 13:30 | 1:30 pm | 17:30 | After hours in Karachi |
| 14:00 | 2:00 pm | 18:00 | After hours in Karachi |
| 14:30 | 2:30 pm | 18:30 | After hours in Karachi |
| 15:00 | 3:00 pm | 19:00 | After hours in Karachi |
| 15:30 | 3:30 pm | 19:30 | After hours in Karachi |
| 16:00 | 4:00 pm | 20:00 | After hours in Karachi |
| 16:30 | 4:30 pm | 20:30 | After hours in Karachi |
| 17:00 | 5:00 pm | 21:00 | After hours in Karachi |
| 17:30 | 5:30 pm | 21:30 | Outside both |
| 18:00 | 6:00 pm | 22:00 | Outside both |
| 18:30 | 6:30 pm | 22:30 | Outside both |
| 19:00 | 7:00 pm | 23:00 | Outside both |
| 19:30 | 7:30 pm | 23:30 | Outside both |
| 20:00 | 8:00 pm | 00:00 (next day) | Outside both |
| 20:30 | 8:30 pm | 00:30 (next day) | Outside both |
| 21:00 | 9:00 pm | 01:00 (next day) | Outside both |
| 21:30 | 9:30 pm | 01:30 (next day) | Outside both |
Office hours taken as 09:00–17:30 in London and 09:00–17:00 in Karachi, which are the customary hours in each city rather than a generic nine to five.