Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and times online free. Convert dates to Unix timestamps in seconds or milliseconds instantly.
How to Use Unix Timestamp Converter
- 1Enter a Unix timestamp (e.g. 1700000000) to convert to a readable date.
- 2Or enter a date and time to convert to a Unix timestamp.
- 3Select "seconds" or "milliseconds" for the timestamp format.
- 4View the result in UTC, your local time, and ISO 8601 format.
- 5The "Current timestamp" display shows the live Unix time updated every second.
About Unix Timestamp Converter
The Unix Timestamp Converter translates between Unix epoch timestamps (seconds or milliseconds since January 1, 1970 UTC) and human-readable date/time strings. Shows the converted time in UTC, your local timezone, and any selected timezone. Includes the current timestamp updated in real time.
Frequently Asked Questions
- What is a Unix timestamp?
A Unix timestamp (also called Unix time or POSIX time) is the number of seconds that have elapsed since the Unix Epoch: January 1, 1970, 00:00:00 UTC. It is timezone-independent and universally used in databases, APIs, and programming languages to store dates as a single integer.
- What is the difference between seconds and millisecond timestamps?
Unix timestamps traditionally count seconds. JavaScript's Date.now() returns milliseconds (1,000× larger). When you see a 13-digit number like 1713100800000, it is milliseconds; a 10-digit number like 1713100800 is seconds. The converter handles both.
- Why is 1970-01-01 the Unix Epoch?
The date was chosen by the early Unix developers as a convenient reference point when designing the time representation for Unix Version 6. It had no deep significance — it was simply a recent, round date that kept timestamps as small positive numbers for the foreseeable future.
- What is the Year 2038 problem?
Many older 32-bit systems store Unix timestamps as a signed 32-bit integer, which overflows on January 19, 2038 at 03:14:07 UTC. Modern 64-bit systems are not affected. The converter uses JavaScript 64-bit floats, supporting dates well beyond the year 2038.
- How do I get the current Unix timestamp?
Click the "Use Now" button to populate both fields with the current time and its Unix timestamp. In code: JavaScript: Math.floor(Date.now()/1000), Python: import time; int(time.time()), PHP: time(), SQL: UNIX_TIMESTAMP(), Unix shell: date +%s.
- What is ISO 8601 format?
ISO 8601 is the international standard for representing dates and times (e.g. 2024-04-14T12:00:00.000Z). The "Z" suffix denotes UTC. It is sortable as a string, unambiguous, and widely supported by APIs, databases, and programming languages.
- Why does my converted date show the wrong time?
Timestamps are stored in UTC, but display in your local timezone. A timestamp of 1713100800 is April 14, 2024 12:00:00 UTC. In New York (UTC−4), this displays as 08:00:00 local time. The ISO 8601 output always shows UTC (ending in Z) to avoid timezone ambiguity.
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Last updated: May 2, 2026 — Unix Timestamp Converter by CalcDash.