Unix Timestamp Converter
Convert Unix timestamps to dates and back in your browser. Auto-detects seconds vs milliseconds, shows ISO 8601, UTC, relative time.
About this tool
Convert between Unix epoch timestamps and human-readable dates, in both directions from the same box. Paste a timestamp (seconds, milliseconds, microseconds, and nanoseconds are auto-detected from the digit count) to get the full date breakdown, or paste an ISO date to get the epoch values.
The report covers what a debugging session actually needs: epoch seconds and milliseconds, ISO 8601, RFC-style UTC, relative time from now, plus the weekday, day of year, and ISO week number.
Common uses
- Decode created_at epoch values from an API response or database row.
- Convert a log line's timestamp to see how long ago it happened.
- Get the exact epoch seconds for a date to use in a query or JWT claim.
Automate via API
The same conversion is available as a REST endpoint for scripts, pipelines, and backends:
curl -X POST https://payloadly.com/api/v1/tools/unix-timestamp-converter \ -H "Content-Type: text/plain" \ -H "X-Api-Key: YOUR_API_KEY" \ --data-binary @input.txt
Frequently asked questions
Is my data uploaded to a server?
No. This tool runs entirely in your browser using JavaScript, and there are no ads on the page. Nothing you paste or drop here is uploaded, logged, or stored, and you can verify that yourself: open your browser's developer tools and watch the Network tab while you convert (no requests leave the page), or disconnect from the internet after the page loads and keep working.
How do you tell seconds from milliseconds?
By digit count. Current Unix time is 10 digits in seconds and 13 in milliseconds, and the tool reports which interpretation it used, so a wrong guess is visible immediately. 16-digit microsecond and 19-digit nanosecond values (common in Go and databases) are detected the same way.
What is Unix time, exactly?
The number of seconds elapsed since the Unix epoch, 1970-01-01T00:00:00 UTC, ignoring leap seconds. It is timezone-free by definition, which is why it is the standard exchange format: the same instant is the same number everywhere, and timezones only apply when displaying it.
Is there a size limit or a fee?
The browser tool is free with no signup and comfortably handles files up to tens of megabytes (limited by your device's memory). For automated or bulk processing inside your own scripts and pipelines, use the paid REST API.
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