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Yes. Press Cmd or Ctrl+K to open tool search, use / from the homepage, and use per-tool shortcuts (shown in the UI) such as jj for JSON and hh for HTML where configured.

What is the difference between seconds and milliseconds?

Unix timestamps in seconds are usually 10 digits (e.g. 1703152000). Millisecond timestamps are 13 digits (e.g. 1703152000000). Spoold auto-detects both; use Now (s) or Now (ms) buttons to insert the current time in either unit.

Timestamp Converter Online — Unix Epoch to Date & UTC

Guide: Timestamp Converter Online

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What is this tool?

Spoold's free timestamp converter online converts between Unix timestamps (epoch seconds or milliseconds) and human-readable dates. Paste a number like 1703152000 to get UTC, local time, ISO 8601, and RFC 2822—or paste a date string to get the epoch back. Also called a unix timestamp converter, epoch converter, or unix time converter. Everything runs client-side in your browser.

Related search terms

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Conversion examples

Try these in the converter above—seconds, milliseconds, and ISO strings are auto-detected.

Input	Type	Result
1703152000	Unix seconds (10 digits)	→ UTC Thu Dec 21 2023 …
1703152000000	Unix milliseconds (13 digits)	Same instant as above
2024-12-21T10:00:00Z	ISO 8601	→ Unix seconds & ms
0	Epoch zero	1970-01-01 00:00:00 UTC

Formats & timezones

Output includes Unix seconds, Unix milliseconds, ISO 8601 (UTC), ISO local, RFC 2822, readable date/time strings, and relative time ("2 hours ago"). Pick a zone (UTC, US/Eastern, Europe/London, Asia/Tokyo, etc.) to see how the same instant prints in that region.

Digits	Unit	Example
10	Seconds since epoch	1703152000
13	Milliseconds since epoch	1703152000000

Remember: DST shifts are reflected via IANA names, but legislative changes can lag browser updates—double-check critical legal timestamps at the source authority.

Use cases

Log debugging — Decode epoch numbers from server logs, Docker, or Kubernetes output.
JWT expiry — Convert exp / iat claims to readable time (pair with JWT decode).
API responses — Turn database created_at integers into UTC for support tickets.
Cron & schedules — Correlate wall time with cron expressions.
Cross-timezone meetings — See the same instant in PT, UTC, and JST before sending invites.

How to use

Paste epoch seconds, epoch milliseconds, or an ISO/RFC date string into the input.
Inspect derived formats on the right; switch timezone from the dropdown as needed.
Use Now (s) / Now (ms) for quick baselines.
Copy any output row, or Save/History to reuse frequent conversions.

FAQ

What is a timestamp converter online?

A timestamp converter online turns Unix epoch numbers (seconds or milliseconds since 1970-01-01 UTC) into human-readable dates and back. Spoold shows UTC, local time, ISO 8601, RFC 2822, and per-timezone formats instantly in your browser.

How do I convert a Unix timestamp to UTC?

Paste the epoch value into the input—for example 1703152000 (seconds) or 1703152000000 (milliseconds). The converter displays UTC along with ISO and readable formats for that instant.

Seconds vs milliseconds?

10-digit Unix times are usually seconds; 13-digit values are milliseconds. Spoold auto-detects both. Use Now (s) or Now (ms) in the header to insert the current epoch in either unit.

How do I convert epoch to date?

Paste your epoch number. The output panel shows calendar date, weekday, clock time in your selected timezone, plus ISO 8601 and RFC 2822 strings you can copy.

Can I convert a date back to a Unix timestamp?

Yes. Paste an ISO 8601 string (e.g. 2024-12-21T10:00:00Z), RFC 2822, or any parseable date. The tool outputs Unix seconds and milliseconds.

Does it handle leap seconds?

JavaScript Date maps POSIX-style instants; leap-second edge cases follow your engine's behavior—verify with an authoritative time source if required for compliance.

Does it support timezones?

Yes. Choose UTC, US timezones (PT/MT/CT/ET), Europe/London, Europe/Paris, Asia/Tokyo, Asia/Kolkata, Australia/Sydney, and more. DST is handled via IANA timezone names.

Is my data sent to a server?

Conversions run client-side using JavaScript Date and Intl APIs. Nothing is uploaded for the conversion itself.

Core: timestamp converter, timestamp converter online, unix timestamp converter, epoch converter, epoch to date, unix time converter, timestamp to date, timestamp to utc.

Formats: iso 8601 converter, rfc 2822 converter, milliseconds since 1970, posix timestamp, seconds to date, date to unix timestamp.

Ops: log line timestamp decode, jwt iat exp human read, timezone compare tool, utc to local time converter.

Similar tools

Conclusion

Spoold's timestamp converter online is a fast bridge between epoch numbers and localized strings—paste seconds, milliseconds, or ISO dates and copy UTC, ISO, or regional time in one step.