CONVERTERS
Timestamp Converter
Convert Unix timestamps to human-readable dates and back.
UNIX TIME
Convert timestamps locally
Timestamp converter guide
A Unix timestamp (also called epoch time) is the number of seconds since January 1, 1970 UTC — the way most databases, APIs, and logs store time. It is compact and timezone-free, but completely unreadable to humans. This converter turns timestamps into readable dates and back, in seconds or milliseconds, in your local timezone.
The conversion happens locally in your browser — no data leaves your device.
Why timestamps exist
Storing time as a single number solves two problems: it is tiny (10 digits vs a 25-character ISO string) and it is unambiguous — a timestamp is an instant, not a wall-clock reading. Timezones and daylight saving are display concerns; the timestamp itself never changes.
That is why virtually every programming language, database, and API uses epoch time under the hood, even when the surface shows a formatted date.
Seconds vs milliseconds — the classic gotcha
Unix time is defined in seconds, but many systems store milliseconds (JavaScript Date, most NoSQL databases, some APIs). A millisecond timestamp is 1,000 times larger — roughly 1.7 trillion today versus 1.7 billion.
This tool auto-detects: 10-digit numbers are treated as seconds, 13-digit as milliseconds. If you paste a timestamp and the date looks wrong by about 50 years, you probably have the wrong precision — and now you know why.
The 2038 problem
A 32-bit signed integer maxes out at 2,147,483,647 seconds — which is January 19, 2038. Systems still storing timestamps in 32-bit integers will overflow on that date, the same way Y2K threatened two-digit years.
Modern systems use 64-bit integers (fine until the year 292 billion) or store timestamps as strings. It is a legacy concern now, but you will still hear about it — and if you maintain old embedded systems, it is a real deadline.
Timezone handling
A timestamp is UTC by definition — it represents the same instant everywhere. When you convert it, this tool displays it in your local timezone, matching what your operating system uses. The same timestamp converted on a device in Tokyo and one in London shows different local times but the same instant — which is the whole point.
Frequently asked questions
What is a Unix timestamp?
The number of seconds elapsed since January 1, 1970 00:00:00 UTC (the Unix epoch). It represents an exact instant, independent of timezone.
What is the difference between seconds and milliseconds timestamps?
Milliseconds are 1,000× larger. Seconds timestamps are about 10 digits; millisecond timestamps are about 13 digits. JavaScript and many databases use milliseconds.
How do I convert a timestamp to a date?
Paste it into this tool — it auto-detects seconds vs milliseconds and shows the local date and time instantly.
What happens on January 19, 2038?
32-bit signed integer timestamps overflow, breaking systems that still use them. Modern 64-bit systems are unaffected for billions of years.
Are timestamps affected by timezones?
No — a timestamp is the same instant everywhere. Only its display as a local date/time changes with your timezone.
Privacy note: timestamp conversion happens in your browser. Your values are not submitted to NAB Tools.