Timestamp Converter

About the Timestamp Converter

A Unix timestamp is the number of seconds elapsed since 1 January 1970 00:00:00 UTC — the "epoch". Computers everywhere store time this way because a plain integer has no time zones, no locale formats, and no ambiguity: 1700000000 means the same instant in Tokyo, Toronto, and Bengaluru. Nearly every API, database, and log system you touch speaks timestamps.

This converter works both directions: paste a timestamp to see it as a readable local and UTC date, or pick a date to get its timestamp (in seconds or milliseconds — the millisecond form is what JavaScript’s Date.now() returns and what many APIs actually send). It also shows the current live timestamp, useful for expiry calculations.

Common gotchas the tool surfaces: reading seconds as milliseconds lands you in January 1970 (a five-digit result), and forgetting UTC produces off-by-hours confusion when sharing times across teams.

Databases add their own conventions worth knowing. MySQL stores DATETIME as a wall-clock string (time-zone blind) and TIMESTAMP as UTC under the hood (converted per session); PostgreSQL recommends timestamptz for anything real-world; and APIs increasingly standardise on ISO 8601 strings while still epoch-encoding inside. The practical habit: store and compute in UTC, render in the user\’s zone, and let this converter arbitrate whenever a stored value and a displayed value disagree.

How to use the Timestamp Converter

1. 1 Paste a Unix timestamp into the input — seconds or milliseconds both work.
2. 2 Read the human date in your local timezone and in UTC instantly.
3. 3 To convert the other way, use the date picker; the timestamp updates in seconds and milliseconds.
4. 4 Use the live "now" readout to sanity-check expiry math before writing cron jobs or token logic.

Key features

Who uses the Timestamp Converter?

• Backend developers debugging API responses and JWT exp (expiry) claims.
• Database work: converting stored epoch values during data audits.
• DevOps reading log timestamps across time zones during incident response.
• QA verifying that schedule jobs, reminders, and cache TTLs fire at the intended instant.
• Writing cron expressions or rate-limit windows against concrete epoch ranges.

Tips and best practices

• Ten digits = seconds, thirteen digits = milliseconds. If a date shows 1970, you passed milliseconds where seconds were expected (or vice versa).
• Always compute, store, and transmit in UTC; convert to a timezone only for display. This one habit prevents most time bugs.
• JWT exp and iat claims are seconds — multiply by 1000 before comparing with Date.now() in JavaScript.
• The 2038 problem: 32-bit signed second counters overflow in January 2038; prefer 64-bit or millisecond storage in new systems.
• For durations (TTLs, retries), add seconds to Date.now()/1000, never parse display strings — parsing is where formats betray you.

Frequently asked questions