Unix Timestamp Converter
Convert Unix seconds or milliseconds to dates and ISO dates back to timestamps. Free, with no signup or usage-count limits.
Free · No signup · No watermark · On-device processing
Use the tool
How to use Unix Timestamp Converter
- Choose timestamp-to-date or ISO-date-to-timestamp conversion.
- For numbers select seconds or milliseconds; for dates include Z or a timezone offset.
- Run the conversion and review UTC, local display and both numeric units.
Understand the input and output
Unix time counts from 1970-01-01T00:00:00Z. Select seconds or milliseconds explicitly. Date input requires an ISO timestamp with Z or a numeric timezone offset to avoid ambiguous local interpretation.
Leap seconds are not represented by JavaScript dates. Very distant dates outside the browser date range are rejected.
Privacy and browser support
Your input is handled in this browser tab. Selected files and entered text are not sent to Varento Tools by this tool. Some specialized libraries load only when needed. A browser with JavaScript and sufficient device memory is required. Read our local-processing explanation.
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Frequently asked questions
Is this tool free without daily usage limits?
Yes. Varento Tools has no signup, accounts, usage-count caps, paywalls or watermarks. Device memory, format support and browser restrictions can still limit technically demanding files.
Why does my local date differ from UTC?
A timestamp represents an instant. The local display uses your device timezone, so the date and clock can differ from UTC while representing the same instant.
Is my input uploaded?
No. This tool processes your input in the current browser tab and does not send it to a processing server.
What are the practical limits?
Leap seconds are not represented by JavaScript dates. Very distant dates outside the browser date range are rejected.