Timestamp Converter

1. Choose a direction: Timestamp → Date or Date → Timestamp.
2. For Timestamp → Date, paste a Unix timestamp and pick a unit — Auto-detect, Seconds or Milliseconds — or select Try sample.
3. For Date → Timestamp, type a date/time such as 2023-11-14T22:13:20Z or 2023-11-14, and choose whether a date/time with no zone should be read as Local time or UTC.
4. The result updates as you type: an ISO string, UTC date/time, local date/time, and Unix seconds and milliseconds. Copy or download the result.

What Timestamp Converter does: it is a free Unix timestamp converter and epoch converter for converting a timestamp to date or a date to timestamp, entirely in your browser.

Seconds vs milliseconds. A Unix timestamp counts seconds (or milliseconds) since 1 January 1970, 00:00:00 UTC. 1700000000 (10 digits) is seconds; 1700000000000 (13 digits) is the same instant in milliseconds. With Auto-detect, a 10-digit-or-shorter number is read as seconds and a 13-digit-or- longer number as milliseconds; an 11 or 12-digit number is genuinely ambiguous, so this tool asks you to pick a unit rather than guessing one and risking a wrong date decades off.

UTC vs local time. UTC is Coordinated Universal Time, the zone-free reference every other time zone is defined relative to. This tool always shows the UTC date/time clearly labeled, and separately shows local date/time — that same moment in the time zone this browser is set to, read from your device, not a named city you pick. Converting Date → Timestamp, a date/time with no explicit zone (no trailing Z) is read using whichever basis — local or UTC — you select; a date/time that already ends in Z is always read as UTC regardless of that choice. A numeric offset such as +05:30 is not accepted — convert the time to UTC and end it with Z instead.

Browser-based processing. No upload is required. Every conversion happens on your own device, in a background worker, and nothing you enter is sent to a server.

What this tool does not do. It does not offer a timezone database with named cities — only UTC and this browser's own local time. It has no calendar widget, no recurring-schedule or cron support, and it does not parse natural-language dates like "next Tuesday". It converts one timestamp or date/time per run; it does not batch-convert a column of values (for that, format your data as CSV or JSON first and use CSV to JSON or JSON to CSV alongside this tool).

Related developer and data tools. Format or validate JSON with JSON Formatter & Validator, or convert between CSV and JSON with CSV to JSON and JSON to CSV. For other everyday encoding tasks, see URL Encode & Decode and Base64 Encode & Decode.