Unix Timestamp to Date & Time Converter
What is Unix Timestamp to Date & Time Converter
A Unix timestamp (also called epoch time or POSIX time) is the number of seconds elapsed since January 1, 1970 at 00:00:00 UTC. It is the universal way computers store and transmit dates and times. This tool converts any Unix timestamp — in seconds or milliseconds — into a human-readable date, showing UTC, local time, ISO 8601 format, and a relative expression like "3 days ago".
How to use
- Paste or type a Unix timestamp into the input field (seconds or milliseconds — the tool auto-detects which).
- See the converted date instantly in UTC, local time, ISO 8601, and relative format.
- Click Now to load the current timestamp.
- Click the copy button next to any row to copy that value to your clipboard.
- Switch to the Date → Unix converter using the link at the bottom to do the reverse conversion.
When to use it
Staring at a created_at value like 1700000000 in a database row and can't tell what it means? Paste it in and you get November 14, 2023 at 22:13:20 UTC right away. It's the fastest way to check a log entry, line up an API response with when something actually happened, or confirm a record's timeline without writing any code.
Frequently asked questions
What is a Unix timestamp?
A Unix timestamp is the total number of seconds (or milliseconds) that have passed since the Unix Epoch: January 1, 1970, 00:00:00 UTC. It is used universally in programming to represent a specific point in time without ambiguity about time zones.
How do I know if my timestamp is in seconds or milliseconds?
Timestamps in seconds have 10 digits (e.g. 1700000000 = year 2023). Timestamps in milliseconds have 13 digits (e.g. 1700000000000). This tool auto-detects: any value of 9,999,999,999 or less is treated as seconds; above that, as milliseconds.
Why is the local time different from UTC?
UTC is the global time standard with no offset. Local time reflects your browser's time zone. For example, if you are in UTC-3, your local time is 3 hours behind UTC. The ISO 8601 output always includes the UTC offset for clarity.
What is the maximum valid Unix timestamp?
The 32-bit signed integer limit is 2,147,483,647, representing January 19, 2038 — the so-called Year 2038 Problem. Modern 64-bit systems support much larger values, but this tool works with any reasonable timestamp you paste in.
Can I convert a negative Unix timestamp?
Negative timestamps represent dates before January 1, 1970. For example, -86400 is December 31, 1969. This tool does not support negative values — for pre-1970 dates, use a dedicated date library.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Share button — anyone who opens the link will see your exact inputs ready to go.
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