Convert Unix timestamps to ISO 8601 UTC dates
Convert epoch seconds and milliseconds into standard ISO 8601, RFC 2822, and local timestamps.
About This Tool
Timestamp to ISO 8601 Converter translates Unix epoch timestamps into standardized UTC ISO 8601 strings (YYYY-MM-DDTHH:mm:ss.sssZ) and readable local dates.
Key Features
ISO 8601 UTC string generation
RFC 2822 and local time formats
Epoch seconds and milliseconds display
Current timestamp generator button
How to Use
- 1Enter a Unix timestamp (10-digit seconds or 13-digit milliseconds) or an ISO date string.
- 2Click Set to Current Time to inspect the present moment.
- 3Copy your desired date format with one click.
Why Use ToolSnippet Timestamp to ISO 8601 Converter?
Quickly debug timestamps in server logs and database records.
Automatically detects seconds vs milliseconds based on digit length.
Provides both UTC and local timezone breakdowns.
Tips for Best Results
- Always store and transmit dates in ISO 8601 UTC format in REST and GraphQL APIs
- Remember that JavaScript Date.now() returns milliseconds, while Unix standard uses seconds
Frequently Asked Questions
How does it detect seconds versus milliseconds?
Timestamps with 10 digits are treated as seconds; 13 digits or more are parsed as milliseconds.
Can I enter a date string to get an ISO timestamp?
Yes, you can enter readable date strings (e.g. 2026-03-16) to convert them to epoch milliseconds and ISO UTC.
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