Developer
JSON Formatter / Validator
Validate, format and compact JSON without uploading your input.
Open toolUnix Timestamp Converter
Convert seconds or milliseconds to UTC, or an explicit ISO date-time to Unix time.
Maximum 200,000 characters. Input is not stored.
Ready. Use Ctrl/⌘ + Enter to run.
Completed and failed run counts are stored only on this device.
How to use this tool
Choose the direction. For date input use ISO 8601 with Z or an explicit offset.
Supported input and limits
Unix conversion uses UTC. Browser Date range and precision apply. A local date without a timezone is rejected. Maximum main input: 200,000 characters.
Frequently asked questions
Does my input leave my browser?
No. A local worker processes it; text and files are not uploaded or stored.
Will this guess seconds versus milliseconds?
No. Select the unit explicitly to avoid ambiguous values.
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