Free Unix Timestamp Converter Online
Convert Unix timestamps to human-readable dates and times, or convert any date and time back to a Unix timestamp. Supports both seconds and milliseconds.
A Unix timestamp is the number of seconds (or milliseconds) that have elapsed since January 1, 1970, at 00:00:00 UTC — the Unix epoch. Almost every programming language, database, and API uses Unix time internally because it is a single integer with no timezone ambiguity. This tool converts any Unix timestamp to a readable date and time in UTC and your local timezone, and it converts any date and time back to a Unix timestamp. It supports both second-precision (10-digit) and millisecond-precision (13-digit) timestamps, which are the two most common formats in production systems.
Unix Timestamp Converter
Timestamp → Date
Auto-detects seconds (10 digits) or milliseconds (13 digits).
Date → Timestamp
How to use this unix timestamp converter
- To convert a timestamp to a date: paste your Unix timestamp into the first input and click Convert. The result shows UTC, local, and ISO 8601 formats.
- To convert a date to a timestamp: use the date-time picker in the second section to select a date and time, then click Convert.
- The tool auto-detects whether your input is seconds or milliseconds based on the number of digits.
- Click Copy next to any result to put it on your clipboard.
Common use cases
- Decoding a timestamp from an API response or database record to see when something happened
- Generating a future timestamp for setting a token expiration or scheduled job
- Debugging log files where events are recorded as Unix timestamps
- Converting a known date (such as a deadline or release date) into a timestamp for use in code
- Checking whether a timestamp is in seconds or milliseconds by seeing the result of both interpretations
Frequently asked questions
What is the Unix epoch?
The Unix epoch is the point in time from which Unix timestamps are counted: midnight at the start of January 1, 1970, in UTC. It was chosen when Unix was designed as a fixed reference point. There is nothing technically special about that date — it is purely a convention.
Are timestamps in seconds or milliseconds?
Both are common. Most system calls and server logs use seconds (a 10-digit number). JavaScript's Date.now() and many web APIs return milliseconds (a 13-digit number). The converter accepts both and auto-detects based on digit count.
Do Unix timestamps account for timezones?
No — a Unix timestamp always represents an absolute moment in UTC. The timezone does not affect the number, only how you display it. Two users in different timezones who record the same event get the same timestamp.
What is the Year 2038 problem?
Old 32-bit systems stored Unix timestamps as a signed 32-bit integer, which overflows in January 2038. Modern 64-bit systems can represent timestamps billions of years into the future. Most modern software is not affected.