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Conversor de fusos horários e planejador de reuniões

Converta um horário para a hora local de até 12 outros fusos, com ajustes de horário de verão e uma grade para planejar reuniões.

Atualizado Exemplos verificados: 4

= 2026-09-29
IANA names (Europe/Paris) or cities from the list, separated by commas.
Mais opções
Experimentar
Converted time
London 10:00 · New York 05:00 · India (Kolkata) 14:30 · Tokyo 18:00
Converted time: London 10:00 · New York 05:00 · India (Kolkata) 14:30 · Tokyo 18:00
UTC
2026-09-29T09:00:00Z
Offset of the source zone
UTC+00:00
Daylight-saving check
Exists once

09:00 on Tue 29 Sep 2026 in UTC is London 10:00 · New York 05:00 · India (Kolkata) 14:30 · Tokyo 18:00. Offsets come from the IANA database, so daylight-saving time on that date is already applied.

Working hours across zones (green = Mon–Fri working hours)

0120591221610232271134238124509135611014672111578312168941317910514181011615191112716201213817211314918221415101923151611200161712211171813222181914233192015042021161521221726222318372301948UTCLondonNew YorkIndia (Kolkata)Tokyo
Meeting planner for Tue 29 Sep 2026 (hours in UTC) Linhas: 24
UTC (from)LondonNew YorkIndia (Kolkata)TokyoIn working hoursNote
00:0001:0020:00 (−1 day)05:3009:001 of 5
01:0002:0021:00 (−1 day)06:3010:001 of 5
02:0003:0022:00 (−1 day)07:3011:001 of 5
03:0004:0023:00 (−1 day)08:3012:001 of 5
04:0005:0000:0009:3013:002 of 5
05:0006:0001:0010:3014:002 of 5
06:0007:0002:0011:3015:002 of 5
07:0008:0003:0012:3016:002 of 5
08:0009:0004:0013:3017:002 of 5
09:0010:0005:0014:3018:003 of 5Selected hour
10:0011:0006:0015:3019:003 of 5
11:0012:0007:0016:3020:003 of 5
12:0013:0008:0017:3021:002 of 5
13:0014:0009:0018:3022:003 of 5
14:0015:0010:0019:3023:003 of 5
15:0016:0011:0020:3000:00 (+1 day)3 of 5
16:0017:0012:0021:3001:00 (+1 day)2 of 5
17:0018:0013:0022:3002:00 (+1 day)1 of 5
18:0019:0014:0023:3003:00 (+1 day)1 of 5
19:0020:0015:0000:30 (+1 day)04:00 (+1 day)1 of 5
20:0021:0016:0001:30 (+1 day)05:00 (+1 day)1 of 5
21:0022:0017:0002:30 (+1 day)06:00 (+1 day)0 of 5
22:0023:0018:0003:30 (+1 day)07:00 (+1 day)0 of 5
23:0000:00 (+1 day)19:0004:30 (+1 day)08:00 (+1 day)0 of 5
Como é calculado S

  1. Source time as UTC

    09:00 on Tue 29 Sep 2026 in UTC is UTC+00:00, so the instant is 2026-09-29T09:00:00Z.

  2. London

    UTC+01:00 → 10:00 on Tue 29 Sep 2026.

  3. New York

    UTC−04:00 → 05:00 on Tue 29 Sep 2026.

  4. India (Kolkata)

    UTC+05:30 → 14:30 on Tue 29 Sep 2026.

  5. Tokyo

    UTC+09:00 → 18:00 on Tue 29 Sep 2026.

Sobre Conversor de fusos horários e planejador de reuniões

The converter reads the wall-clock time you enter in the source zone, subtracts that zone's UTC offset on that date to get a single instant, then adds each target zone's offset at the same instant. Offsets come from the IANA time zone database, so daylight-saving time is applied for the date you pick rather than for today.

The first worked example, 09:00 in New York on 15 January 2026, is 14:00 in London, 19:30 in India and 23:00 in Tokyo. The grid below the result shows all 24 hours of the source day in every zone, green where it falls inside Monday-to-Friday working hours (09:00 to 17:00 unless you change them), so a shared meeting slot is visible at a glance.

Some wall-clock times do not exist or happen twice. On 8 March 2026, 02:30 never occurs in New York and is read as 03:30; on 1 November 2026, 01:30 occurs twice and the first occurrence is used unless you choose the second.

Exemplos resolvidos

9 am in New York in January

Date
2026-01-15
Tempo
09:00
From time zone
New York
Convert to
Asia/Kolkata, Europe/London, Asia/Tokyo
Converted time
India (Kolkata) 19:30 · London 14:00 · Tokyo 23:00
UTC
2026-01-15T14:00:00Z
Offset of the source zone
UTC−05:00
Daylight-saving check
Exists once

Fonte de verificação: Python 3.8 dateutil.tz with system tzdata 2024a: datetime(2026,1,15,9,tzinfo=New_York).astimezone(...)

A time skipped when New York springs forward

Date
2026-03-08
Tempo
02:30
From time zone
New York
Convert to
Europe/London, Asia/Kolkata
Converted time
London 07:30 · India (Kolkata) 13:00
UTC
2026-03-08T07:30:00Z
Daylight-saving check
Skipped by a DST change

Fonte de verificação: Python 3.8 dateutil.tz: datetime_exists(2026-03-08 02:30 New_York) is False; resolve_imaginary gives 03:30 EDT = 07:30Z

A repeated hour when New York falls back, second occurrence

Date
2026-11-01
Tempo
01:30
From time zone
New York
Convert to
Europe/London
If the time happens twice (clocks going back)
Use the second occurrence
Converted time
London 06:30
UTC
2026-11-01T06:30:00Z
Offset of the source zone
UTC−05:00
Daylight-saving check
Occurs twice (DST overlap)

Fonte de verificação: Python 3.8 dateutil.tz: datetime_ambiguous(2026-11-01 01:30 New_York) is True; fold=1 gives 01:30 EST = 06:30Z (fold=0 gives 05:30Z)

Quarter-hour offsets

Date
2026-07-01
Tempo
12:00
From time zone
Kathmandu
Convert to
Pacific/Chatham, America/St_Johns
Converted time
Chatham Islands 19:00 · St John's 03:45
UTC
2026-07-01T06:15:00Z
Offset of the source zone
UTC+05:45

Fonte de verificação: Python 3.8 dateutil.tz: Kathmandu +05:45, Chatham +12:45 (NZ winter), St John's −02:30 (summer time)

Perguntas

What is the difference between UTC and GMT?

On a clock they read the same, but UTC is an atomic time scale and GMT is a time zone. UTC is derived from International Atomic Time and kept within 0.9 seconds of the Earth's rotation by leap seconds; 27 have been added since 1972, the last on 31 December 2016. GMT is the UK's winter civil time; from late March to late October the UK uses BST, which is UTC+01:00.

When do the clocks change for daylight saving time in 2026?

In the United States clocks go forward at 02:00 local time on the second Sunday in March and back on the first Sunday in November, the rule since 2007: 8 March and 1 November in 2026. The EU and UK change at 01:00 UTC on the last Sunday in March and October: 29 March and 25 October. Between 8 and 29 March, New York is 4 hours behind London instead of 5.

Why use a zone name like America/New_York instead of EST?

An IANA name carries the zone's full history of offset and daylight-saving rules; an abbreviation is one fixed offset and is often ambiguous. EST means UTC−05:00, which is wrong for New York from March to November, when it is on EDT (UTC−04:00). IST can mean India (UTC+05:30), Irish or Israel Standard Time, and CST is both US Central and China Standard Time.

Which time zones are offset by 30 or 45 minutes?

India uses UTC+05:30 all year, Iran UTC+03:30, Afghanistan UTC+04:30 and Myanmar UTC+06:30. Nepal is at UTC+05:45 and the Chatham Islands at UTC+12:45, or UTC+13:45 in the southern summer. Newfoundland is at UTC−03:30 in winter and South Australia at UTC+09:30 in winter, and both move by an hour for daylight saving.

How many working hours do London and New York share?

Three hours for most of the year: 09:00 to 17:00 in New York is 14:00 to 22:00 in London, so the shared window is 14:00 to 17:00 London time. It widens to four hours in the weeks when only the US has changed its clocks, such as 8 to 29 March 2026. Tokyo's 09:00 to 17:00 does not overlap either city's working day.

Qual é a precisão de “Conversor de fusos horários e planejador de reuniões”?

A precisão depende dos dados inseridos e das hipóteses do método. O cálculo decimal usa 50 algarismos significativos, mas estimativas, métodos numéricos e dados de origem podem ter menor precisão; o arredondamento exibido não elimina essas limitações. Exemplos resolvidos verificados com fontes independentes: 4. Por exemplo, “9 am in New York in January” é verificado com Python 3.8 dateutil.tz with system tzdata 2024a: datetime(2026,1,15,9,tzinfo=New_York).astimezone(...).

De onde vem o método?

IANA Time Zone Database; ECMA-402 Intl.DateTimeFormat (timeZone option); TC39 Temporal — time zones and resolving ambiguity.

Sobre esta calculadora

tUTC=tlocal−offsetfrom,ttarget=tUTC+offsetto(tUTC)t_{\text{UTC}} = t_{\text{local}} - \text{offset}_{\text{from}},\qquad t_{\text{target}} = t_{\text{UTC}} + \text{offset}_{\text{to}}(t_{\text{UTC}})

Fontes

  1. IANA Time Zone Database
  2. ECMA-402 Intl.DateTimeFormat (timeZone option)
  3. TC39 Temporal — time zones and resolving ambiguity

Verificado com as referências

Esta calculadora inclui 4 exemplos resolvidos com respostas de fontes independentes. Eles fazem parte do conjunto de testes e você também pode executá-los aqui.

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