LazyTools Header
Time Zone Converter — Convert Times & Find Meeting Windows Online | LazyTools
Date & Time Tool

Free Time Zone Converter — Convert Times & Plan Global Meetings

Convert any time between 32 major timezones instantly. Select your source zone, enter the time and up to four target zones — and see converted times with UTC offsets and business-hours status. Furthermore, the Meeting Planner tab builds a 24-hour grid coloured by business-hours overlap, identifying the optimal shared meeting window for any city combination without manual calculation.

32 timezonesUAE & Gulf includedMeeting window plannerDST-awareBusiness hours statusFree & private

How to use the Time Zone Converter

1
Select the source timezone
Choose your source timezone from the From dropdown. Furthermore, Dubai (UAE, UTC+4) is the default — the most common source for LazyTools users. All major Gulf, Asian, European and American zones are listed.
2
Enter the time and date
Type the source time in 24-hour format. Additionally, entering the date is important for DST-observing zones — the UTC offset for London, New York and Sydney changes twice a year, so the date determines the correct offset.
3
Select up to four target timezones
Choose the zones you want to convert to from the four To dropdowns. Furthermore, leave unused dropdowns on the empty option — only filled rows appear in the result table. You can convert to one or all four simultaneously.
4
Click Convert Time
The result table shows each target timezone with the converted time, UTC offset and a business-hours badge. Moreover, the badge highlights in green when the converted time falls within standard business hours (8am–6pm local).
5
Use Meeting Planner for optimal scheduling
Click the Meeting Planner tab and select up to four cities. Furthermore, the 24-hour grid shows the local hour for each city at every UTC time. Best windows — where every city shows business hours — appear highlighted. Chips at the bottom list the best UTC hours explicitly.

Conversion modes: Convert Time versus Meeting Planner

The converter offers two modes for different scheduling needs. Furthermore, each mode is optimised for a specific task — precise single-time conversion or strategic meeting window discovery.

ModeBest forOutput
Convert TimeConverting a specific moment — a call, a deadline, a live eventExact converted time, UTC offset, business-hours badge
Meeting PlannerFinding the optimal recurring meeting slot for 2–4 cities24-hour grid with business-hours colouring; best windows highlighted

Daylight saving time and Gulf zones

Daylight saving time shifts clocks forward by one hour in spring and back in autumn in regions that observe it. Furthermore, this changes the UTC offset twice a year for zones like London, New York and Sydney — so the time gap between the Gulf and these cities changes seasonally. Gulf countries — UAE, Saudi Arabia, Qatar, Kuwait, Bahrain and Oman — never observe DST. Their UTC offsets are fixed year-round, making them stable scheduling anchors.

How timezone conversion is calculated

Every moment in time has a single UTC representation. Converting between zones means adding or subtracting the UTC offset for each zone. Furthermore, the browser's Intl.DateTimeFormat API with IANA timezone identifiers handles DST adjustments automatically based on the date entered.

Converted time = UTC time + Target timezone UTC offset
UTC time = source time minus source timezone's current offset
UAE (Dubai) = UTC+4 always — no DST ever
London (UK) = UTC+0 winter (GMT), UTC+1 summer (BST)
New York = UTC-5 winter (EST), UTC-4 summer (EDT)

Why the date matters for accurate conversion

Zones that observe DST change their UTC offset on specific dates. Furthermore, converting a time without specifying the date can produce an incorrect result if the conversion spans a DST boundary. The tool uses the date you enter to retrieve the correct offset, ensuring accuracy even for times close to DST transition dates in March and October.

Worked example: scheduling a quarterly review across four cities

A company headquartered in Dubai needs a quarterly review with London, New York and Singapore teams. They use the Meeting Planner in winter (London UTC+0, New York UTC-5).

UTC hourDubaiLondonNew YorkSingaporeAll open?
05:0009:0005:0000:0013:00No
09:0013:0009:0004:0017:00No
13:0017:0013:0008:0021:003 of 4
No single UTC hour places all four cities — Dubai, London, New York and Singapore — simultaneously within 9am–5pm business hours. The closest overlap is 13:00 UTC: Dubai at 17:00, London at 13:00, New York at 08:00 (early but workable), Singapore at 21:00 (evening). The meeting planner shows this with a 3/4 overlap score, letting the team decide whether Singapore's evening hour is acceptable.

Gulf to London DST shift impact

Dubai (UTC+4) and London (UTC+0 winter, UTC+1 summer) differ by 4 hours in winter and 3 hours in summer. Furthermore, this changes the optimal meeting window by one hour between the two seasons — a recurring source of confusion for teams that schedule a fixed weekly time and forget to adjust for the DST transition. The converter handles this automatically when you enter the correct date.

What is a time zone converter?

A time zone converter translates a specific time in one timezone to the equivalent in one or more others. Furthermore, it removes the mental arithmetic that makes manual conversion error-prone. Additionally, the output shows not only the converted time but the converted day — since crossing enough time zones can shift the calendar date.

Time zones standardised in the late 19th century. Before standardisation, each city kept its own solar time. Furthermore, railways made this unsustainable — a train timetable requires consistent times across every station it serves. The system that emerged divides the world into 24 primary zones offset from GMT, with modern zones adding half-hour and quarter-hour variants for geographical and political reasons.

Who uses a time zone converter?

Distributed teams convert meeting times for every cross-regional call. Furthermore, this task repeats for every international scheduling event throughout the year. Freelancers communicate availability in their clients' local time. Furthermore, developers verify that timestamps display correctly for users in different regions before releasing code changes.

Travellers convert flight times to destination local time. Financial professionals align trading windows across market time zones. Moreover, live event audiences — sports broadcasts, product launches, conference keynotes — need local start times to know when to tune in.

Gulf timezones at a glance

The Gulf uses two fixed offsets. UAE and Oman use UTC+4. Saudi Arabia, Bahrain, Qatar and Kuwait use UTC+3. Furthermore, no Gulf country observes DST. This stability means that the Gulf's side of any timezone gap never changes — only the DST-observing partner moves, making the Gulf the most predictable anchor for international scheduling in the region.

Why time zone accuracy matters for global businesses

Timezone errors generate missed meetings, failed SLAs and damaged client relationships. A single DST miscalculation — where one party's clock shifted and the other's did not — can derail a high-stakes call. Furthermore, the brief period after DST transitions — when some countries have shifted and others have not — is a particularly high-risk window for international scheduling mistakes.

For UAE-based businesses, the risk is seasonal and predictable. Additionally, the pattern repeats every spring and autumn. The gap between Dubai (UTC+4, fixed) and London changes by one hour in late March and again in late October. Moreover, the gap between Dubai and New York changes on different dates — creating a short window where Europe and America are on different offset changes simultaneously. The Meeting Planner shows the current overlap for any combination without requiring the user to track these transitions manually.

How the meeting planner replaces back-and-forth coordination

Finding a shared meeting time for three or more time zones typically requires multiple messages asking participants to check their availability. The meeting planner eliminates this entirely. Furthermore, it shows every hour of the day with business-hour status for all selected cities simultaneously. The best shared windows appear automatically — no calculation required. Moreover, for recurring weekly meetings this identification needs to happen only once, after which the same slot works every week until a DST transition changes the picture.

Frequently asked questions

Yes. The tool uses the date you enter to determine the correct UTC offset for each timezone on that specific day. Furthermore, it relies on the browser's built-in IANA timezone database, which includes all DST rules globally and updates with the operating system. Gulf timezones — UAE, Saudi Arabia, Qatar, Kuwait, Bahrain and Oman — are always at their fixed offsets regardless of the date, because they never observe DST.
Yes. The tool displays the converted day of the week alongside the time. Converting 22:00 Tuesday in Dubai (UTC+4) to New York (UTC-5) gives 13:00 Tuesday — the same day. Converting the same time to Tokyo (UTC+9) gives 03:00 Wednesday — a day later. Furthermore, the date shift always appears in the result so you never miss a day-change when planning international calls or deadlines.
When cities span many time zones, no single hour places all of them within business hours simultaneously. This is common for combinations such as Dubai, Los Angeles and Tokyo. Furthermore, when no perfect window exists, the planner shows the best partial overlaps — hours where the most cities are in business hours — so you can choose the least-disruptive compromise. The overlap score (e.g. "3/4") makes this visible for every hour.
UTC (Coordinated Universal Time) and GMT (Greenwich Mean Time) are functionally equivalent for scheduling purposes. Both represent the zero-reference timezone from which all offsets are measured. Furthermore, UTC is the modern standard used in computing, APIs and aviation. GMT is still used conversationally, particularly in the UK. This tool uses UTC as the reference throughout, which produces the same result as GMT-based calculations.
No — the gap changes with the seasons. In winter, London is at UTC+0 and Dubai is at UTC+4, giving a 4-hour difference. In summer, London shifts to UTC+1 (BST), so the gap narrows to 3 hours. Furthermore, this seasonal shift occurs in late March (London springs forward) and late October (London falls back). The converter uses the date you enter to apply the correct offset automatically, so you always get an accurate conversion.

Related Date & Time tools

Every tool on LazyTools runs in your browser. Nothing is uploaded or stored.

World Clock

Live time in 34 cities simultaneously. Furthermore, a sweet-spot grid shows business-hour overlaps at a glance.

Military Time Converter

Convert 12-hour to 24-hour time. Additionally, batch mode converts an entire schedule at once.

Business Days Calculator

Count working days with UAE, Gulf and US holiday calendars. Moreover, add N business days to any start date.

UNIX Timestamp Converter

Convert Unix timestamps to readable dates in any timezone. Furthermore, natural language input and code snippets are included.

Date Difference Calculator

Exact gap between two dates in every unit. Additionally, milestone markers show every 100th and 1000th day.

UTC Offset Converter

Find the UTC offset for any timezone by name. Furthermore, see DST-adjusted offsets month by month.

Rate this tool

4.6
out of 5
336 ratings
5 ★
73%
4 ★
21%
3 ★
4%
2 ★
1%
1 ★
1%
How useful was this tool?