Best Free Online Timestamp Converter
Unix timestamps — the number of seconds (or milliseconds) since January 1, 1970 UTC — are the standard way to represent dates and times in APIs, databases, logs, and JWT tokens. But a number like 1735689600 is meaningless without converting it to a human-readable date. devtoolkit.sh's Timestamp Converter does this instantly in both directions: enter a Unix timestamp to see the corresponding date and time in UTC and your local timezone, or enter a date and time to get the corresponding Unix timestamp. Both seconds and milliseconds are supported, with automatic detection based on the magnitude of the input. The tool also shows the ISO 8601 formatted string and the relative time (e.g., "3 days ago" or "in 2 hours"), which is especially useful when debugging logs and API responses. All conversion happens client-side using your browser's Date API. This makes it particularly useful for interpreting log timestamps from servers in different time zones, verifying JWT expiration times, and debugging date-related bugs in APIs that store timestamps as integers.
FAQ
- What is a Unix timestamp?
- A Unix timestamp is the number of seconds elapsed since January 1, 1970 00:00:00 UTC (the Unix epoch). It is a universal, timezone-independent way to represent a moment in time.
- How do I know if my timestamp is in seconds or milliseconds?
- Unix timestamps in seconds are typically 10 digits (e.g., 1735689600). Millisecond timestamps are 13 digits. The converter auto-detects the format.
- Does it show my local timezone?
- Yes. The converter shows the datetime in both UTC and your browser's local timezone, as detected from your device settings.