Timestamp Converter
Developer ToolsConvert a Unix timestamp (seconds or milliseconds) to a readable date, or a date and time back to a timestamp — computed locally in your browser.
Timestamp → Date
Seconds or milliseconds since Jan 1, 1970 UTC.
Date → Timestamp
What a Unix timestamp actually is
A Unix timestamp (also called epoch time) is the number of seconds that have elapsed since midnight UTC on January 1, 1970 — the "Unix epoch." Rather than storing a date as a year, month, and day, most databases, APIs, and programming languages store moments in time as this single, unambiguous number, which sidesteps the ambiguity of formatted dates (is 03/04/2026 March 4th or April 3rd?) and makes it trivial to compare two moments in time or calculate a duration between them with simple subtraction.
You'll see it in two flavors: seconds (the original Unix standard, still used by most server-side systems and APIs) and milliseconds (used by JavaScript's own Date object and many web APIs). Mixing the two up is a common source of bugs — a millisecond timestamp treated as seconds resolves to a date over 50,000 years in the future, which is usually the tell that something was interpreted in the wrong unit.
Why this comes up so often in development
Timestamps show up constantly in logs, database records, and API responses, and they're rarely stored in a format anyone can read directly at a glance. Debugging why a record has a strange date, checking exactly when a token expires, or converting a value pulled from an API response into something human-readable are all everyday moments where converting a raw timestamp by hand — accounting for time zones correctly — is slow and error-prone enough that a dedicated converter earns its keep.
Local time, UTC, and why both matter
A Unix timestamp itself has no time zone — it's a single global count of seconds — but converting it into a date requires picking a time zone to display it in. This tool shows both the local time (your browser's system time zone) and UTC (Coordinated Universal Time) side by side, since server logs and API documentation are conventionally written in UTC, while you're usually trying to relate that to your own local clock. Mixing these up is another common source of off-by-several-hours confusion when debugging a timestamp that looks technically correct but doesn't match what you expected to see.
How to use Timestamp Converter
- 1Paste a Unix timestamp and choose seconds or milliseconds, or pick a date and time.
- 2Read the converted result in local time, UTC, and ISO 8601.
- 3Copy whichever value you need.
Frequently asked questions
Is a Unix timestamp in seconds or milliseconds?
It depends on the system — traditional Unix/POSIX timestamps and most APIs use seconds, while JavaScript's Date.now() and many web APIs use milliseconds. If a timestamp resolves to a date far in the future or past, you likely have the unit swapped.
Does a Unix timestamp include time zone information?
No — it's a single number representing an exact moment in time, with no time zone attached. The time zone only comes into play when converting it into a displayed date.
What is ISO 8601?
A standardized, unambiguous date-and-time text format (e.g. 2026-07-31T14:22:00.000Z) widely used in APIs and logs, distinct from a raw numeric Unix timestamp.
Is my data sent anywhere when I convert a timestamp?
No — the conversion runs locally in your browser using JavaScript's built-in Date object.
Why does a timestamp of 0 mean January 1, 1970?
That date and time (midnight UTC) is the fixed reference point, or "epoch," that Unix time counts forward from — timestamp 0 is, by definition, that exact moment.