Time Difference Calculator Between Cities
Convert any date and time between 2 to 6 cities or time zones, see the shared work hours on a 24-hour grid, check upcoming daylight saving changes, and share the result or add it to your calendar.
New York and London: 5 hours apart most of the year
London is 5 hours ahead of New York, or 4 hours for a few weeks around the DST changes in March and late October. Live times load in your browser.
Clocks load in your browser.
New York
America/New_York
--:--
London
Europe/London
--:--
24-hour overlap grid
The grid shows one row per city over the same 24 hours, shades night, early/late and work hours, and outlines the hours every city shares. It loads in your browser.
Daylight saving changes in the next 12 months
Upcoming clock changes for each city are calculated in your browser.
Hour-by-hour conversion
A 24-row table for the selected day loads in your browser.
How to use the time difference calculator
- 1Add 2 to 6 cities or zones
Search any city worldwide or pick an IANA time zone from the list. The first city is the base; the star button makes another city the base.
- 2Pick a date and time
Choose a date and time in the base city, or click an hour on the grid. Every city is converted with the UTC offset and daylight saving rules in force at that moment, from your browser's time zone data.
- 3Find shared work hours
Set each city's work hours (9:00 to 17:00 by default). The 24-hour grid outlines the window everyone shares, or the tool suggests the closest slot when there is none.
- 4Share or save the slot
Copy a link with the cities and time, download an .ics file or open Google Calendar, or export the hour-by-hour table as CSV.
How to calculate the time difference between two places
Solar time moves one hour for every 15 degrees of longitude, but clocks follow civil time zones set by law. Each zone is defined as an offset from Coordinated Universal Time (UTC), and that offset can change during the year with daylight saving time (DST). So a time difference always belongs to a specific moment:
A positive result means B is ahead of A. The calculator above resolves both offsets for the date and time you pick, using the IANA zone of each city and the time zone rules built into your browser, so a meeting next spring is converted with next spring's offsets, not today's.
Why the time difference changes with daylight saving
Two places keep a constant gap only if they change clocks on the same dates, or neither changes at all. When their DST dates differ, the gap moves by an hour for the weeks in between:
- March: the US and Canada move clocks forward on the second Sunday of March; the UK and EU on the last Sunday. For those two to three weeks the US–UK gap is 1 hour shorter (New York–London 4 hours instead of 5).
- Late October to early November: Europe falls back on the last Sunday of October, North America on the first Sunday of November, so the gap is 1 hour shorter for one week.
- Opposite hemispheres: Australia and New Zealand use DST during the southern summer, so the gap to Europe or North America swings by up to 2 hours across the year (London–Sydney runs from 9 to 11 hours).
- Zones without DST (India, Japan, China, Arizona, Hawaii and many more) shift by 1 hour against any place that does use it.
The dates for the current year are calculated in your browser from its built-in time zone rules.
Daylight saving rules by region
These are the current rules. Governments do change them, sometimes with little notice; the calculator relies on the rules in your browser, which are updated with browser and operating system updates.
When clocks change
Current DST rules for the regions most often compared.
| Region | DST starts | DST ends | Notes |
|---|---|---|---|
| United States and Canada (most areas) | 2nd Sunday in March, 2:00 local time | 1st Sunday in November, 2:00 local time | Each zone changes at its own 2 AM, so New York changes 3 hours before Los Angeles. |
| European Union | Last Sunday in March, 01:00 UTC | Last Sunday in October, 01:00 UTC | All EU zones change at the same instant. |
| United Kingdom and Ireland | Last Sunday in March, 01:00 UTC | Last Sunday in October, 01:00 UTC | Same rule as the EU. |
| Australia: NSW, Victoria, ACT, Tasmania (and South Australia) | 1st Sunday in October, 2:00 standard time | 1st Sunday in April, 3:00 daylight time | Queensland, Western Australia and the Northern Territory do not use DST. |
| New Zealand | Last Sunday in September, 2:00 | 1st Sunday in April, 3:00 | Southern Hemisphere: summer time runs across the new year. |
| No DST | n/a | n/a | Most of Asia including India, China, Japan, South Korea, Singapore and the UAE; most of Africa; Russia; Brazil; most of Mexico (since 2022); Arizona (except the Navajo Nation); Hawaii. |
Example: finding a meeting time across three time zones
A team in New York, London and Berlin wants a call inside everyone's 9:00 to 17:00 working day. Convert each working day to UTC, then take the latest start and the earliest end.
Overlap = [max(start_i in UTC), min(end_i in UTC)], empty if the start is not before the end- Latest start: max(14:00, 09:00, 08:00) = 14:00 UTC
- Earliest end: min(22:00, 17:00, 16:00) = 16:00 UTC
- Overlap: 14:00–16:00 UTC = 2 hours
- In local time: 9:00–11:00 New York, 14:00–16:00 London, 15:00–17:00 Berlin
- In summer all three move forward 1 hour together, so the local window is the same
- In the weeks when only the US is on DST (March, and late October to early November), New York works 13:00–21:00 UTC: the overlap becomes 13:00–16:00 UTC, 3 hours (9:00–12:00 New York, 13:00–16:00 London, 14:00–17:00 Berlin)
Schedule the recurring call at 9:00 or 10:00 New York time and it stays inside everyone’s working day all year.
Add San Francisco (09:00–17:00 PST is 17:00–01:00 UTC) and there is no shared window at all: London's day ends at 17:00 UTC exactly when San Francisco's starts, and the same happens in summer. With all four cities the closest one-hour slot in winter and summer is 8:00 AM San Francisco (11:00 AM New York, 4:00 PM London, 5:00 PM Berlin): an hour early for San Francisco and an hour late for Berlin. The calculator does this for you: it outlines the shared window on the 24-hour grid, or, when there is none, suggests the slot that stays closest to everyone's work hours.
Time difference between major business cities
January and July offsets follow each zone's current rules (January is winter in the north and summer in Australia). The last column is calculated by your browser for today.
Financial centers: UTC offsets and difference from New York
January and July by rule; today from your browser's time zone data.
| Market | Zone | January | July | vs NY (Jan) | vs NY (Jul) | Today |
|---|---|---|---|---|---|---|
| New York (NYSE) | Eastern Time (EST / EDT) | UTC−5 | UTC−4 | 0 h | 0 h | … |
| São Paulo (B3) | Brasília Time (no DST) | UTC−3 | UTC−3 | +2 h | +1 h | … |
| London (LSE) | GMT / BST | UTC+0 | UTC+1 | +5 h | +5 h | … |
| Frankfurt (Xetra) | CET / CEST | UTC+1 | UTC+2 | +6 h | +6 h | … |
| Dubai (DFM) | Gulf Standard Time (no DST) | UTC+4 | UTC+4 | +9 h | +8 h | … |
| Mumbai (NSE) | India Standard Time (no DST) | UTC+5:30 | UTC+5:30 | +10 h 30 min | +9 h 30 min | … |
| Singapore (SGX) | Singapore Time (no DST) | UTC+8 | UTC+8 | +13 h | +12 h | … |
| Hong Kong (HKEX) | Hong Kong Time (no DST) | UTC+8 | UTC+8 | +13 h | +12 h | … |
| Tokyo (TSE) | Japan Standard Time (no DST) | UTC+9 | UTC+9 | +14 h | +13 h | … |
| Sydney (ASX) | AEDT / AEST | UTC+11 | UTC+10 | +16 h | +14 h | … |
Popular city pairs
Each link opens the calculator with both cities loaded. The rules below explain why the gap is not always the same.
- New York to London time difference
London is 5 hours ahead; 4 hours for 2 to 3 weeks in March and 1 week from late October to early November.
- New York to Los Angeles time difference
Los Angeles is 3 hours behind all year; both follow the US DST dates.
- New York to India time difference
India is 10 h 30 min ahead in US winter and 9 h 30 min ahead during US daylight saving time.
- Los Angeles to Tokyo time difference
Tokyo is 17 hours ahead in US winter and 16 hours during US daylight saving time.
- London to Sydney time difference
Sydney is 11 hours ahead in the northern winter, 9 hours in the northern summer, and 10 hours for a few weeks in between.
- London to Dubai time difference
Dubai is 4 hours ahead while the UK is on GMT and 3 hours during British Summer Time.
- Chicago to London time difference
London is 6 hours ahead; 5 hours in the weeks when only the US is on daylight saving time.
- New York to Paris time difference
Paris is 6 hours ahead; 5 hours in the weeks when only the US is on daylight saving time.
- Toronto to London time difference
London is 5 hours ahead; 4 hours in the same March and late-October weeks as New York.
- Los Angeles to Manila time difference
Manila is 16 hours ahead in US winter and 15 hours during US daylight saving time.
- Singapore to London time difference
London is 8 hours behind while on GMT and 7 hours behind during British Summer Time.
- Berlin to New York time difference
New York is 6 hours behind; 5 hours in the weeks when only the US is on daylight saving time.
Time zone abbreviations vs IANA IDs
Abbreviations are convenient but not unique, and they do not tell you when a zone changes its clocks. The same letters mean different things in different countries:
- CST: US Central Standard Time (UTC−6), China Standard Time (UTC+8) or Cuba Standard Time (UTC−5).
- IST: India Standard Time (UTC+5:30), Irish Standard Time (UTC+1, Ireland's summer time) or Israel Standard Time (UTC+2).
- BST: British Summer Time (UTC+1) or Bangladesh Standard Time (UTC+6).
- AST: Atlantic Standard Time (UTC−4) or Arabia Standard Time (UTC+3).
IANA time zone IDs such as America/Chicago, Asia/Shanghai or Asia/Kolkata name one region and carry its full history of offsets and DST rules, which is why calendars and this calculator use them. When a zone has no widely used abbreviation, browsers show a numeric one such as GMT+5:45. You can pick an IANA ID directly in the calculator or search a city and let it find the zone.
Time zones with 30- and 45-minute offsets
Not every zone is a whole number of hours from UTC. The calculator handles these to the minute:
30-minute offsets
• India and Sri Lanka: UTC+5:30 all year.
• Iran: UTC+3:30 (DST abolished in 2022).
• Afghanistan: UTC+4:30 all year.
• South Australia and Northern Territory: UTC+9:30; South Australia uses UTC+10:30 in summer.
• Newfoundland, Canada: UTC−3:30, UTC−2:30 in summer.
45-minute offsets
• Nepal: UTC+5:45 all year.
• Chatham Islands, New Zealand: UTC+12:45, UTC+13:45 in summer.
• Eucla, Western Australia: UTC+8:45, an unofficial local time.
Limitations of time difference calculations
- Offsets and DST dates come from the time zone data in your browser. If a country changes its rules (as Mexico did in 2022), an out-of-date browser can be wrong until it is updated.
- A searched city is matched to a zone with generalized time zone polygons, so a place within about a kilometer of a zone border can get the neighboring zone. Pick the IANA ID directly if you know it.
- Times skipped when clocks spring forward are moved forward by the gap (2:30 AM becomes 3:30 AM); times that happen twice when clocks fall back use the first occurrence.
- Work hours default to 9:00–17:00 on every day. The calculator does not know weekends or public holidays, and some countries work Sunday to Thursday.
Related Time and Navigation Tools
Check your live local timezone with What Time Zone Am I In? or explore daylight patterns on the Live Day and Night Map.
Quick facts about the time difference calculator
| Fact | Value | Notes |
|---|---|---|
| Time Zone Database | IANA tz database (browser ICU data) | Global timezone authority |
| DST handling | Offsets for the chosen date | Lists each zone's next clock change within 12 months |
| Work hours | 9:00 AM – 5:00 PM local by default | Editable per city; shared window shown in each local time |
Edge cases and exceptions
Half-Hour & 45-Minute Time Zones
Locations like India (UTC+5:30), Iran (UTC+3:30), Adelaide (UTC+9:30), and Nepal (UTC+5:45) have fractional hour offsets. The tool handles non-integer offsets precisely.
Asymmetric Daylight Saving Transitions
The US switches to DST on the second Sunday of March, while Europe switches on the last Sunday of March. For 2 to 3 weeks in March and 1 week from late October to early November, US–Europe time differences are 1 hour shorter.
The time difference calculator: worked examples
New York to London Remote Work
Scenario: Scheduling team meetings between New York (UTC-5, UTC-4 in summer) and London (UTC+0, UTC+1 in summer), both working 9:00 to 17:00.
Outcome: Most of the year London is 5 hours ahead, so 9:00 AM – 12:00 PM in New York overlaps 2:00 – 5:00 PM in London (3 shared hours). In the weeks when only the US is on daylight saving time the gap is 4 hours and the overlap grows to 4 hours (9:00 AM – 1:00 PM New York, 1:00 – 5:00 PM London).
Frequently asked questions about the time difference calculator
How is time difference calculated?
For the date and time you choose, the tool looks up each city's UTC offset from its IANA time zone using your browser's time zone rules, including daylight saving time, and subtracts one offset from the other.
Why is the time difference between the US and UK 4 hours some weeks?
The US moves clocks forward on the second Sunday of March and back on the first Sunday of November; the UK changes on the last Sundays of March and October. Between those dates only the US is on summer time, so New York is 4 hours behind London instead of 5: for 2 to 3 weeks in March and 1 week around the start of November.
How do I calculate the time difference between two cities?
Subtract each city's UTC offset for the same moment. If London is UTC+0 and New York UTC-5, New York is five hours behind.
What are overlapping business hours?
They are the hours when every location is inside its work hours at the same moment, such as 9 a.m. to 5 p.m. local. The tool outlines that window on its 24-hour grid and lists it in each city's local time; you can change the work hours per city.
Does the time difference change with daylight saving time?
Yes, whenever two places change clocks on different dates or only one of them uses daylight saving time. New York and London are usually 5 hours apart but 4 hours for a few weeks a year; India is 10 h 30 min ahead of New York in winter and 9 h 30 min in summer. The tool lists each zone's next clock change and how the gap shifts.
What time is it in one city when it is 9 am in another?
Make the second city the base, set the date and 9:00, and read the other cities' times in the list or on the grid. The answer depends on the date, because daylight saving time can move the gap by an hour, so pick the actual day of your call.
Can I add the meeting to my calendar?
Yes. Pick the time, choose a length, then download an .ics file (Outlook, Apple Calendar and most others) or open a prefilled Google Calendar event. The event is stored in UTC, so each calendar shows it in its owner's local time.
Can I compare more than two cities?
Yes, up to six. Each city gets its own row on the 24-hour grid and its own work hours, and the shared window must fit all of them.
Which countries do not use Daylight Saving Time?
Many, including China, Japan, India, Russia and Brazil. Most of Arizona and all of Hawaii also stay on standard time.
How do I convert time zones in Excel or Google Sheets?
Add or subtract the offset hours divided by 24 from the base time. Use a UTC column to avoid mistakes.
What is the biggest time difference on Earth?
Up to 26 hours. Baker Island at UTC-12 and Kiritimati (Line Islands) at UTC+14 are the two extremes, so the same moment can be a different calendar day in each place.
How do I find a meeting time across time zones?
Add every city, set each one's work hours and pick the date. The tool converts each work day to the same UTC timeline and outlines the hours they all share; if there is none, it suggests the slot closest to everyone's work hours. Click a column to select it, then copy the link or add it to a calendar.
Is the time shown live?
The world clocks are live and use your device's clock. The converter starts at the current time, but you can pick any date and time, and a shared link keeps the time you chose.
Keep exploring
What to do with this result
- What Time Zone Am I In?Use this to check your current time zone.
- World Time Zone MapUse this to view the world time zone map.
- US Time Zone MapUse this to view the US time zone map.
- Sunrise and Sunset Times CalculatorUse this to check sunrise and sunset times.
- Live World Day and Night Map (Solar Terminator)Use this to see the live day and night map.
Blog posts, studies & methodology
Browse counties by state
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Puerto Rico
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming