Toolivaro

Free Time Zone Converter

Convert any date and time between IANA time zones with correct daylight-saving handling and explicit offsets.

Processed locally in your browser

How is the result calculated?

Scheduling with a client: 14:00 Warsaw → New York

A 14:00 meeting in Warsaw (Europe/Warsaw, UTC+2 in summer) is 12:00 UTC — and 08:00 in New York (America/New_York, UTC−4 in summer). The converter shows all three at once: the target time, the UTC instant, and the offsets, so the invitation can be double-checked instead of guessed.

Input Value
date 2026-08-04
time 14:00
from Europe/Warsaw
to America/New_York
Result 08:00 America/New_York · 12:00 UTC · Warsaw UTC+02:00 · New York UTC−04:00

What is the formula and its assumptions?

Conversion method

target time = source wall time − source offset + target offset

Symbol Meaning
source offset UTC offset of the source zone at that instant
target offset UTC offset of the target zone at that instant

Offsets are read from the IANA time-zone database at the specific instant, so DST transitions on either side are handled correctly.

Offsets

offset(zone, instant) = local wall time − UTC time, in minutes

Symbol Meaning
instant the exact moment being converted

What are the most common mistakes?

  • Using fixed abbreviations that change meaning between regions or seasons.
  • Assuming the offset of a zone is constant across the year — DST changes it.
  • Converting with the wrong date: the offset depends on the specific day, not just the hour.

What are the assumptions and limitations?

  • The converter uses your browser’s embedded IANA data — extremely rare future rule changes require a browser update to be reflected.
  • Historical time-zone changes before the database’s coverage are resolved with the closest known rules.
  • The converter works with a single instant; recurring meetings across DST boundaries need the meeting-overlap planner.

Where do the numbers come from?

Last reviewed August 4, 2026 · Version 1.0.0 · Toolivaro does not guarantee external content.

Time Meeting Overlap Planner Find the time windows when teams in different time zones can meet, using their local work hours and DST-aware math. Time Business Days Calculator Count business days between dates or add business days to a date — weekends and your own holidays excluded. Time Date Difference Calculator Calculate the exact number of days, weeks, months, and years between two dates — with a single trusted method.

Frequently asked questions

Why not use "CST" or other abbreviations?

Abbreviations are ambiguous — "CST" is Central Standard Time, China Standard Time, and Cuba Standard Time. IANA identifiers like America/Chicago name one zone unambiguously, which is why this converter only uses them.

What happens to a time that does not exist locally (spring forward)?

The converter uses the standard convention: the local time shifts forward by the skipped hour (for example 02:30 becomes 03:30). The page flags this so the result is never silently surprising.

Does the converter know the current offset?

It computes the offset at the exact instant you convert, not a fixed offset — so a date in January and a date in July can have different offsets for the same zone, which is exactly how DST works.

Found a mistake or have a correction? Report it — we review every correction.