Convert a Unix timestamp into a readable date — shown in both your local time and UTC — or go the other way and turn a date and time into an epoch value. It detects seconds versus milliseconds automatically, and runs entirely on your device.
Enter a timestamp to convert it to a date.
The epoch is 1970-01-01 00:00:00 UTC. Values with 13+ digits are treated as milliseconds.
How it works
A Unix timestamp counts the seconds since 1 January 1970 00:00:00 UTC, the “epoch”. To convert one, the tool multiplies seconds to milliseconds, builds the instant, and formats it two ways: your local time (with your time zone) and UTC. It also shows the exact ISO 8601 string, the form most APIs and databases store.
Going the other way, a date and time you pick — interpreted in your local zone — becomes an epoch in both seconds and milliseconds. Because seconds and milliseconds look similar, the converter treats any value with 13 or more digits as milliseconds; you can override that with the unit selector.
Practical examples
Reading a timestamp from a log
Paste 1700000000 and the tool shows it’s 2023-11-14 22:13:20 UTC — plus the same instant in your local time, so a log line stops being an opaque number.
Milliseconds from JavaScript
A value like 1700000000000 (13 digits) is auto-detected as milliseconds — the form Date.now() returns — and converted to the same 2023-11-14 instant rather than a date thousands of years out.
Getting the epoch for a specific moment
Switch to date-to-timestamp, pick a date and time, and copy the epoch in seconds for a config, a JWT exp claim, or an API query.
Frequently asked questions
What is a Unix timestamp?
It’s the number of seconds elapsed since the Unix epoch — midnight UTC on 1 January 1970. It’s a compact, timezone-free way to represent an instant, which is why logs, databases and APIs use it so widely.
Seconds or milliseconds — how does it know?
By magnitude. A seconds timestamp for the current era has 10 digits; the millisecond version has 13. The tool auto-detects based on that, and you can force seconds or milliseconds with the unit selector if a value is ambiguous.
Why show both local time and UTC?
A timestamp is a single instant, but people read it in a place. UTC is the canonical value stored in systems; your local time is what the moment actually was for you. Showing both avoids the off-by-hours confusion time zones cause.
Which time zone does date-to-timestamp use?
The date and time you enter are interpreted in your browser’s local time zone, then converted to the epoch. If you need a specific zone, adjust the input accordingly or work from a UTC value.
Does it handle dates before 1970?
Yes. Timestamps before the epoch are negative, and the converter handles them, so you can enter a negative value or a pre-1970 date and get a sensible result.
What is the “year 2038 problem”?
Systems that store Unix time in a signed 32-bit integer overflow on 19 January 2038. This tool uses JavaScript numbers, which don’t have that limit, so it converts dates well beyond 2038 without issue.
What format is the ISO string?
ISO 8601 in UTC, like 2023-11-14T22:13:20.000Z — the “Z” marks UTC. It’s the format most databases and APIs expect, and it sorts correctly as plain text.
Is the timestamp I enter kept private?
Yes. All conversion runs in your browser; nothing is uploaded and analytics never receives the values.
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