time calculator

Timezone Converter

Convert a meeting time between two UTC offsets without memorizing the difference between PST, EST, GMT, or IST.

Results

Target year
2025.00
Target month
2.00
Target day
10.00
Target hour
15.00
Target minute
0.00
Readable time
2025-02-10 15:00 (UTC+1)

Overview

When your team spans San Francisco, London, and Bangalore, a simple calendar invite can turn into mental math and mistakes. Time zones, daylight saving changes, and half‑hour offsets make it easy to schedule meetings at the wrong hour or on the wrong day.

This timezone converter focuses on the essentials: give it a local date and time plus the UTC offset of your source and destination timezones, and it returns the converted date and time along with a readable label you can paste into invites or chat. It’s a lightweight helper for remote teams, travelers, SREs, and anyone coordinating across time zones without memorizing every offset or relying solely on browser clocks.

How to use this calculator

  1. Enter the local year, month, day, hour, and minute for the time you are starting from (for example, your own timezone).
  2. Enter the source UTC offset for that date—remember to use the DST-adjusted value where applicable (e.g., −4 for EDT, not −5).
  3. Enter the destination UTC offset for the timezone you want to convert into.
  4. Run the conversion to see the corresponding date and time in the target offset, including any day changes from crossing midnight.
  5. Copy the readable label into meeting invites or chat so teammates can see the target time without doing their own mental math.
  6. Repeat with additional destination offsets if you want to sanity-check times across multiple regions (for example, US, Europe, and APAC).

Inputs explained

Date/time
The starting local date and time in the source timezone. Use a 24‑hour clock for hour (0–23) to avoid ambiguity between AM and PM when entering times.
From UTC offset
The offset of your source timezone relative to UTC (for example, −8 for PST, −7 for PDT, 0 for UTC/GMT, +1 for CET, +5.5 for IST). Supports half‑hour and quarter‑hour offsets.
To UTC offset
The offset of the target timezone relative to UTC. Enter the DST-adjusted value for the date you care about if that region observes daylight saving time.

How it works

You enter a specific calendar date and time along with a source UTC offset (for example, −5 for Eastern Standard Time, −4 for Eastern Daylight Time, +1 for Central European Time, or +5.5 for India).

The converter treats your input as local time in the source offset and converts it to UTC by subtracting the source offset from the local time to get a neutral reference point.

It then applies the destination UTC offset to that UTC timestamp, effectively shifting the time into the target timezone while automatically handling day changes (for example, crossing midnight or rolling into the next or previous day).

Half‑hour and quarter‑hour time zones are supported by entering offsets like +5.5, −3.5, or +5.75, which covers places such as India, Newfoundland, and Nepal without needing a timezone database.

Finally, the calculator outputs the target year, month, day, hour, and minute, plus a preformatted "Readable time" label that you can copy into calendar descriptions, Slack messages, documentation, release runbooks, or handoff notes.

Because the model uses simple offsets rather than named timezones, you stay in full control of daylight saving time: you specify the correct offset for the date in question, which keeps the logic transparent and easy to audit.

Formula

Target time = Source time − Source offset + Target offset

When to use it

  • Scheduling recurring meetings across continents without miscounting hours or forgetting DST adjustments.
  • Coordinating deployment windows, trading sessions, or maintenance periods that must align across multiple regions.
  • Checking arrival or departure times when flights are listed in local times but planning happens in another timezone.
  • Helping remote teammates visualize their local time for a given event when writing documentation or announcements.
  • Verifying handoff times for customer support, incident response, or on‑call rotations that span timezones.
  • Planning global webinars, product launches, or live streams so promotional materials list accurate times for all target audiences.
  • Reconciling logs or monitoring alerts that are stored in UTC with human conversations that happen in local time, especially during incident reviews.

Tips & cautions

  • Always check whether the date you’re converting falls in standard time or daylight time for each region, and adjust the offsets accordingly (for example, −5 vs −4 for Eastern, +1 vs +2 for Central Europe).
  • Half-hour zones like IST (+5.5) and NT (−3.5) are supported—enter the decimal offset instead of rounding to a full hour.
  • If you only know local offsets in hours and minutes, convert minutes to decimals (30 minutes = 0.5, 45 minutes = 0.75) before entering them.
  • For recurring events around DST changes, plan separate entries on each side of the change to see how local times shift in different regions, and double‑check directly in your calendar platform.
  • Include the UTC time and offset in your invites (for example, "15:00 UTC / 10:00 ET / 16:00 CET") to reduce confusion when people travel or DST rules change.
  • When in doubt, anchor everything in UTC first and use this tool to derive local times; treating UTC as your source of truth reduces off‑by‑one‑hour mistakes.
  • No automatic DST rules or named timezone lookup—offsets must be entered manually based on your knowledge of local time for that date.
  • Assumes the Gregorian calendar and simple UTC-based offsets; it does not model historical timezone changes or unusual local rules.
  • Does not show multiple target zones at once—you need to run separate conversions for each additional region you want to check.
  • Does not validate whether an offset actually exists for a real-world timezone; it trusts the values you provide.
  • Intended as a convenience tool, not as a legal or operational timekeeping authority for high-stakes systems.
  • Does not account for leap seconds or extremely rare timezone changes that can occur when governments update local time policies.
  • Keeps precision at the minute level; if your use case depends on sub‑minute timing, you should rely on system APIs or specialized libraries.

Worked examples

9:00 AM EST to CET

  • Source: Feb 10, 2025 at 09:00 with a source offset of UTC−5 (Eastern Standard Time).
  • Convert to UTC: 09:00 + 5 hours = 14:00 UTC.
  • Apply destination offset UTC+1 (Central European Time): 14:00 + 1 hour = 15:00 on Feb 10, 2025.
  • Readable label might be: "15:00 CET (09:00 EST on Feb 10)" for your invite.

IST to PST

  • Source: Jan 5, 2025 at 18:30 with a source offset of UTC+5.5 (India Standard Time).
  • Convert to UTC: 18:30 − 5.5 hours = 13:00 UTC.
  • Apply destination offset UTC−8 (Pacific Standard Time): 13:00 − 8 hours = 05:00 on Jan 5, 2025.
  • Interpretation: a 18:30 IST call lands at 05:00 PST the same day, which may not be practical for West Coast teammates.

Crossing midnight from US to APAC

  • Source: Mar 3, 2025 at 20:00 with a source offset of UTC−8 (Pacific Standard Time).
  • Convert to UTC: 20:00 + 8 hours = 04:00 UTC on Mar 4.
  • Destination: UTC+9 (Japan Standard Time) → 04:00 + 9 hours = 13:00 on Mar 4, 2025.
  • Interpretation: an evening meeting in California on Mar 3 shows up as early afternoon on Mar 4 in Japan—crossing both midnight and the calendar date.

Deep dive

This timezone converter shifts any local date/time between UTC offsets so you can quickly see what a meeting or event looks like for teammates in another region. Enter the source time and both offsets (for example, −5 to +1) to get the converted date, time, and a readable label.

It’s ideal for remote teams, travel planning, and global release coordination when you want a lightweight tool that respects half‑hour offsets and lets you control daylight saving time by choosing the correct offset for each date.

Use it alongside your calendar or scheduling app to double‑check cross‑timezone invites, confirm handoff times, and avoid the classic "I thought that was my time" mishaps that happen around DST changes.

FAQs

Does it know daylight saving time?
Not automatically. You choose the correct offset for the date you care about (for example, −5 for Eastern Standard Time in winter or −4 for Eastern Daylight Time in summer). This keeps the logic simple and makes it easy to see exactly which offset you’re using, but it also means you should double‑check DST dates when converting times near those transitions.
Can I use named timezones?
This calculator works with numeric UTC offsets only. To use a named timezone like "America/New_York" or "Europe/Berlin," first look up its offset for the specific date (taking DST into account) and then enter that offset here.
Can I convert to multiple time zones at once?
Not in a single run. Enter one destination offset, note the result, then change the offset to the next region you care about. Many people keep the same source time and run through a short list of offsets when planning global meetings.
How do I handle 30- or 45-minute offsets?
Enter them as decimals, such as +5.5, −3.5, or +5.75. The calculator works with fractional offsets so you can model regions that are not aligned to the hour.
Does the date roll over automatically?
Yes. If the conversion crosses midnight, the target date rolls forward or backward as needed. Always pay attention to the day as well as the clock time when scheduling early‑morning or late‑night events across timezones.

Related calculators

This timezone converter uses simple UTC offsets and does not automatically incorporate daylight saving rules, historical timezone changes, or jurisdiction-specific policies. It is intended for everyday coordination and planning, not as a definitive timekeeping authority for legal, financial, or safety‑critical systems. Always double‑check critical schedules—especially around DST transitions—using your calendar system and, when needed, confirm times directly with participants.