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Unix Timestamp Converter online, free
Convert Unix epoch timestamps in seconds and milliseconds to UTC and local date-time strings, or parse ISO 8601 datetimes to timestamps.
- Runs in your browser — no upload
- Free, no sign-up, no watermark
- TXT
How to use Unix Timestamp Converter · Unix Timestamp Converter — frequently asked questions
How to use Unix Timestamp Converter
- 1
Add your TXT file
Drop a file on the page, paste it, or click Select Files. Nothing is uploaded — it opens straight in your browser.
- 2
Fine-tune the settings
Set unix timestamp, timestamp unit and iso 8601 date (optional) in the Fine-tune panel, or keep the defaults — they suit most files.
- 3
Run Unix Timestamp Converter
Press the start button. Processing happens on your device, usually in seconds.
- 4
Download the result
Save the finished file, or continue with another tool without downloading in between.
What Unix Timestamp Converter can do
- Unix Timestamp — Numeric timestamp in seconds or milliseconds
- Timestamp Unit: seconds and milliseconds
- ISO 8601 Date (Optional) — Convert an ISO date string (e.g. 2026-10-30T12:00:00Z) to Unix timestamp
- Private by design — files are processed in your browser and never uploaded
- Free with no sign-up, no watermark and no daily limit
Unix Timestamp Converter — frequently asked questions
What is a Unix timestamp?
A Unix timestamp (or Epoch time) counts the total number of seconds elapsed since January 1, 1970 at 00:00:00 UTC, not counting leap seconds. It provides a standard, timezone-independent representation of moments in time.
Can I convert both seconds and milliseconds?
Yes. The converter seamlessly handles 10-digit timestamps (seconds) and 13-digit timestamps (milliseconds), automatically detecting the unit or allowing explicit selection.
Can I convert ISO 8601 date strings to Unix timestamps?
Yes. You can supply an ISO 8601 formatted date (e.g., 2026-10-30T12:00:00Z) or standard date string to compute the corresponding Unix timestamp in both seconds and milliseconds.
Does this tool support local time zone conversions?
Yes. The converter outputs formatted dates in both Coordinated Universal Time (UTC) and your device's local system time zone, alongside relative time indicators (e.g., "in 2 hours" or "5 minutes ago").
Is my data kept private?
Yes. All date parsing and timestamp calculations are executed 100% locally in your web browser. No dates, timestamps, or personal data are ever uploaded or transmitted to any server.
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