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Timestamp Converter

The timestamp converter turns Unix timestamps, milliseconds, ISO dates, local time and UTC into practical date formats. All calculations run locally in the browser.

Convert timestamps

Enter a Unix timestamp, ISO date or local date. The tool detects the format automatically or uses the selected input type.

Leave empty and use ā€œCurrent timeā€ or enter your own value.

Ready
Unix time - No valid value detected yet.

Formats

Format Value

Conversion notes

  • Unix seconds count seconds since 1 January 1970 at 00:00:00 UTC.
  • Unix milliseconds are common in JavaScript.
  • Local time depends on the browser time zone.
  • UTC is the neutral reference time for servers, APIs, logs and databases.

Time zones, DST and detected type

A Unix value identifies an instant; the local display is determined by the browser time zone. ISO values with Z or a numeric offset carry time-zone information. A value without an offset and German local date input are interpreted in the browser's local time. Daylight-saving transitions, repeated times and nonexistent local times are not resolved by this tool; the browser runtime applies its own rules.

In Auto mode, whole numbers with an absolute value of at least 100,000,000,000 are treated as milliseconds and smaller whole numbers as seconds. This is a practical heuristic, not reliable type information. For small or unusual values, select seconds or milliseconds explicitly. Negative values before the Unix epoch and 0 are accepted when they stay within the JavaScript Date range.

The selectable fixed offsets are display values such as +02:00 or -05:00; they are not named IANA time zones and do not apply their own DST rules. The POSIX specification defines the Unix epoch; RFC 3339 explains UTC and numeric offsets.

Examples and limits

  • 0 corresponds to 1970-01-01T00:00:00.000Z. 1719835200 seconds and 1719835200000 milliseconds identify the same instant.
  • 2026-07-10T12:00:00Z is a UTC instant; its local display can differ by machine.
  • Invalid calendar dates such as 31.02.2026, unparseable text, values outside the Date range and assumptions about leap seconds must not be silently reused as valid results.
  • Conversion, preview, clipboard and export run locally in the browser. No time-zone or time server is queried.