Unix Timestamp Converter
A free online Unix timestamp converter — convert Unix time to a date, or convert a date to a Unix timestamp. Auto-detects seconds vs. milliseconds. Unix time, POSIX time, and epoch time are all the same value; this tool handles them interchangeably.
Current Unix timestamp
Milliseconds: 1700000000000
Timestamp → Date
- UTC
- 2023-11-14 22:13:20
- Local
- 2023-11-14 22:13:20 UTC
- ISO 8601
- 2023-11-14T22:13:20.000Z
- RFC 2822
- Tue, 14 Nov 2023 22:13:20 +0000
- Day of week
- Tuesday
Date → Timestamp
- Seconds
- 1767268800
- Milliseconds
- 1767268800000
- UTC
- 2026-01-01 12:00:00
- ISO 8601
- 2026-01-01T12:00:00.000Z
Date to Unix timestamp
To convert a date to a Unix timestamp, pick the date and time zone on the right side of the converter above. The result is the number of seconds (or milliseconds) between 1970-01-01T00:00:00Z and your chosen moment. The tool handles DST transitions correctly because it uses the IANA tz database via Luxon.
Convert Unix time to UTC
A Unix timestamp is already in UTC — there is no time zone to "convert from". The converter above shows the human-readable UTC form (e.g. 2026-06-02T18:42:23Z) in the UTC row of the result panel. For ISO 8601 specifically, see the ISO 8601 validator + builder.
Unix time, POSIX time, and epoch time
All three names refer to the same value: the number of seconds since January 1, 1970 UTC. POSIX is the formal standard, Unix is the historical operating-system name, and "epoch time" is the everyday programmer term. This converter accepts any of them — they are interchangeable as a number. For the full history and the Y2038 problem, see What is epoch time?
Epoch milliseconds vs. epoch seconds
Standard Unix time is in seconds (10 digits today). JavaScript's Date.now(), Java's System.currentTimeMillis(), and many JSON APIs use milliseconds (13 digits). This tool detects the unit by digit count and converts in both directions automatically. See Epoch time in code for the seconds-vs-milliseconds idiom in each major language.
Frequently asked questions
- What is a Unix timestamp?
- A Unix timestamp (also called epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970 at 00:00:00 UTC, excluding leap seconds. It is the standard machine-readable way to represent a moment in time because it is a single integer with no time-zone ambiguity.
- How do I convert a Unix timestamp to a date?
- Paste the Unix timestamp into the left input on this page. The tool decodes it into UTC, your local time, and ISO 8601 format instantly. It works for both seconds (10 digits, e.g. 1700000000) and milliseconds (13 digits, e.g. 1700000000000) — the unit is auto-detected.
- How do I convert a date to a Unix timestamp?
- Pick a date and time zone on the right side of the converter. The tool generates the matching Unix timestamp in both seconds and milliseconds. The "date to epoch" direction is just as fast as the reverse — both run client-side using the IANA time zone database.
- How do I convert Unix time to UTC?
- A Unix timestamp is already in UTC by definition — it is the seconds since 1970-01-01T00:00:00Z. The "UTC" output row on this page shows the human-readable UTC date and time for any Unix timestamp you paste. For example, 1748876543 corresponds to 2026-06-02T18:42:23Z.
- Is "POSIX time" the same as Unix time?
- Yes. POSIX time, Unix time, and epoch time are three names for the same thing: an integer counting the seconds since January 1, 1970 UTC. POSIX is the formal standards-body name, Unix is the historical name from the operating system, and "epoch time" is the everyday programmer term.
- Is the timestamp in seconds or milliseconds?
- This tool auto-detects: any integer with 13 or more digits is treated as milliseconds, otherwise as seconds. You can paste either format. Most APIs use seconds; JavaScript Date.now() and most JVM languages use milliseconds.
- What is the current Unix timestamp?
- The clock at the top of this page shows the current Unix timestamp live. It updates every second and never leaves your browser. You can also click the "Now" button to fill the current epoch into the converter input.
- Is this Unix time converter free?
- Yes. This is a free online Unix timestamp converter. Every calculation runs entirely in your browser — no sign-up, no server round-trip, no tracking of your timestamps. Bookmark this page if you need a permanent reference.