Unix Timestamp & Epoch Converter — Developer Reference
Why use a Unix Timestamp Converter?
Unix timestamps are the universal language of time in software. Every major programming language, database, and API uses epoch time internally. Epoch Converter gives you instant, accurate conversions — entirely in your browser with zero server calls.
Whether you're debugging a JWT exp claim, reading a Kafka offset, or validating a cron schedule, converting a raw number to a readable date in the right timezone is a daily developer task.
- Auto Unit DetectionDetects seconds, milliseconds, microseconds, and nanoseconds automatically — no digit-counting required.
- Any TimezoneSearch 400+ IANA timezones by name. Results update instantly as you switch.
- Privacy-FirstAll conversions run in your browser. No timestamps leave your device.
What is a Unix Timestamp?
A Unix timestamp (epoch time) is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC — known as the Unix epoch. It is timezone-agnostic and language-agnostic, making it the canonical format for storing and exchanging time in software.
Most modern systems use milliseconds (13 digits in 2024) for sub-second precision, especially JavaScript where Date.now() returns milliseconds. This tool auto-detects the unit based on digit count: ≤11 → seconds, 12–14 → milliseconds, 15–17 → microseconds, 18+ → nanoseconds.
Get the Current Timestamp in Any Language
Quick reference for getting the current Unix epoch in common languages:
Common Use Cases
Epoch timestamps appear everywhere: JWT tokens (exp, iat, nbf claims), HTTP headers (Last-Modified, If-Modified-Since), database records (created_at, updated_at), log files, cron schedules, and distributed tracing.
Negative timestamps are valid — they represent dates before January 1, 1970. For example, -86400 = December 31, 1969, 00:00:00 UTC.
Output Formats Explained
Each timestamp is shown in four formats:
- ISO 8601 —
2024-04-09T08:00:00+05:30— the standard for APIs, databases, and interchange. - RFC 2822 —
Tue, 09 Apr 2024 08:00:00 +0530— used in email headers and HTTP. - Local — formatted in the selected IANA timezone.
- UTC — the raw canonical representation.
- Relative — human context like "2 years ago" or "in 3 days".
The Y2K38 Problem
On January 19, 2038 at 03:14:07 UTC, 32-bit signed integers used to store Unix timestamps will overflow and wrap to a large negative number — interpreted as December 13, 1901. This is the Year 2038 (Y2K38) problem.
Modern 64-bit systems are not affected. This tool uses JavaScript's 64-bit float arithmetic and is safe well beyond year 275,760. If you maintain legacy C code or old MySQL schemas using INT(11) for timestamps, plan your migration now.
Timezone Handling
Unix timestamps are always UTC under the hood — they count seconds from January 1, 1970 UTC with no timezone offset. The timezone only matters when displaying a human-readable representation.
This tool uses the browser's Intl.DateTimeFormat API to format timestamps in any of 400+ IANA timezones (e.g. America/New_York, Asia/Kolkata) accurately, including DST transitions. Your local timezone is detected automatically and pinned at the top of the selector.
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