Dates & Scheduling

Unix Timestamp Converter

Convert a Unix timestamp into a readable date and convert dates back into Unix time. Seconds and milliseconds are supported, and nothing leaves your browser.

Runs in your browser v1.0.0

Actions

live

Your timezone

Local time

Search real IANA time zones such as America/New_York or Asia/Kolkata. The chosen zone is used to read the date you type and is added as an extra row so you can compare UTC, local time, and your own zone at a glance. Defaults to your device timezone.

Timestamp → Date

Unix time

Paste seconds (10 digits) or milliseconds (13 digits). Negative values are valid for dates before 1970. Fractional seconds are accepted.

Input unit

Date → Timestamp

ISO 8601

Use ISO 8601 such as 2024-01-31T12:00:00Z. Values without a time zone are read in the timezone selected above, so pick your own zone to convert wall-clock times the way you expect.

How it works

All conversion happens in your browser with the native Date object and Intl timezone data — nothing is uploaded and no external service is called. Unix time counts whole seconds since 1970-01-01T00:00:00Z, ignoring leap seconds, so the millisecond value is always the second value multiplied by 1000. Outputs are shown in UTC, your device’s local time, and any IANA timezone you choose, so you can compare them at a glance. Date strings without an explicit offset are interpreted in the selected timezone.

Practical uses

Convert Unix seconds or milliseconds to readable dates and back again.

Common ways to use it

  • Read an epoch value from an API response as an ISO date.
  • Convert a target date into a Unix timestamp for a request or config.
  • Compare the same instant in UTC, local time, and a chosen IANA zone.

Unix seconds to UTC and New York

Input

1700000000 (seconds)

Output

2023-11-14T22:13:20.000Z
2023-11-14 22:13:20 UTC
2023-11-14 17:13:20 in America/New_York (UTC-05:00)

Verified with the tool's parse and format functions. The same instant formatted in America/New_York is 17:13:20 because that date is in standard time (UTC-05:00).

Options that matter

  • Input unit — Auto-detect, Seconds, or Milliseconds; auto-detect treats values of 1,000,000,000,000 or more as milliseconds.
  • Timezone — pick an IANA zone to read date inputs without an offset and to add a comparison row.
  • Date input and date picker — convert the other direction; values without an offset use the selected zone.
  • Use current time / Copy all / Download report — fill or export the combined results.

Things to keep in mind

  • Time-zone display uses the browser's Intl data, so results vary with the browser time-zone database.
  • Timestamp values are rounded to the nearest millisecond and must fall inside the native Date range of roughly 100,000,000 days either side of 1970.
  • Unix time ignores leap seconds, so a day is always treated as 86,400 seconds.