Timestamp Converter
Convert Unix timestamps (seconds or milliseconds) and datetime-local values in your browser using the Date API—timezone is your browser local time; no custom format picker.
Result
Tips
Seconds vs milliseconds
Unix time is often 10 digits (seconds). JavaScript and many APIs use 13 digits (milliseconds). Use the milliseconds toggle when needed.
Browser local timezone
The datetime-local field and Date conversion use your browser's local timezone—not a selectable custom zone.
No custom format picker
This tool does not offer custom strftime-style output formats; it converts between Unix numbers and datetime-local.
Client-side only
Conversion uses the browser Date API; values are not sent to a Toolomix timestamp API.
Unix ↔ datetime-local
Convert between a Unix timestamp and a datetime-local control.
Seconds or milliseconds
Toggle whether the numeric timestamp is treated as seconds or milliseconds.
Browser Date API
All math runs with the client-side Date object in your local timezone.
What this tool does
Timestamp Converter turns a Unix timestamp (seconds or milliseconds) into a datetime-local value, or the reverse, using the browser Date API.
Timezone is your browser local time. It is not a custom date-format formatter and does not call a server.
How to use
Pick a direction
Choose Timestamp → Date or Date → Timestamp.
Enter the value
Paste a Unix number or set the datetime-local field.
Set seconds or milliseconds
Toggle milliseconds when your value is in ms instead of seconds.
Read the result
Review the converted value in the UI (local timezone via browser Date).
Supported inputs and output
Input: a numeric Unix timestamp (seconds or milliseconds) or a datetime-local date/time. Output: the other form via client-side Date conversion.
There is no file upload and no custom output-format string builder.
Processing and privacy
All conversion runs in your browser using the Date API.
Your values are not sent to Toolomix for conversion—there is no timestamp-converter API endpoint for this page.
Limitations
Known limits
- Timezone is browser local only—no custom timezone picker
- No custom format picker (strftime-style patterns are not available)
- Seconds vs milliseconds must be chosen correctly
- Range and precision follow the browser Date implementation
- Text/number UI only—no file upload
Troubleshooting
If the date looks wrong by orders of magnitude, switch between seconds and milliseconds.
If the datetime-local field looks off relative to UTC logs, remember this UI uses your browser's local timezone.
Frequently Asked Questions
Does this upload my timestamps?
No. Conversion runs in your browser with the Date API. There is no timestamp-converter API call for this page.
What timezone is used?
Your browser's local timezone. There is no separate timezone picker for custom zones.
Can I choose a custom date format?
No. This tool converts between Unix seconds/milliseconds and the datetime-local input—there is no custom format picker.
Why does my timestamp show the wrong date?
Check seconds vs milliseconds (roughly 10 vs 13 digits). Using the wrong unit shifts the result far into the past or future.
What is the Unix epoch?
January 1, 1970, 00:00:00 UTC. Unix timestamps count seconds or milliseconds since that moment.
Are negative timestamps supported?
They are subject to what the browser Date object accepts for your input. Extreme values may be invalid or imprecise.
How do I convert JWT exp/iat claims?
Those claims are usually Unix seconds. Paste the number here (seconds mode), or decode the token first with JWT Decoder.
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Convert Unix timestamps and datetime-local values in your browser's local timezone.
