Epoch and Unix time converter

Convert timestamps in seconds or milliseconds to local time and UTC.

What is Unix time?

Unix time, also called epoch time, is a linear count of seconds since 1 January 1970 00:00:00 UTC. Because it ignores time zones and daylight-saving adjustments, it is the foundation for timestamps in APIs, databases, and operating systems.

Key properties

  • Unix time ignores leap seconds, so official clocks occasionally pause to realign.
  • Most APIs use milliseconds (ms) or seconds (s). HashyTools accepts both.
  • 64-bit epoch values handle dates well beyond the year 2038.
  • It is timezone-agnostic—display layers decide how to localize.

Common conversions

Operation Formula
Seconds → milliseconds ms = seconds × 1000
Milliseconds → ISO 8601 new Date(ms).toISOString()
Date to epoch (JavaScript) Date.parse('2025-01-01T00:00:00Z') / 1000

Conversion playbook

Use the tool for quick lookups, then integrate these approaches when you need timestamps inside scripts or automation pipelines.

API debugging

Paste token expiration claims or webhook timestamps to verify whether they fall before or after your current time in UTC and local zones.

Database migrations

Confirm conversions between integer epoch columns, SQL datetime types, and application-level timezones before running data migrations.

Scheduler logs

Translate cron execution times into local business hours so on-call teams instantly understand incident windows.

Check seconds versus milliseconds

The values 1704067200 seconds and 1704067200000 milliseconds both represent 2024-01-01T00:00:00.000Z.

JavaScript — UTC result

console.log(new Date(1704067200 * 1000).toISOString());
// 2024-01-01T00:00:00.000Z

Python 3 — UTC result

from datetime import datetime, timezone
print(datetime.fromtimestamp(1704067200, timezone.utc).isoformat())
# 2024-01-01T00:00:00+00:00

Select the unit explicitly when converting. Local time depends on your device timezone; UTC represents the same instant everywhere. This page converts a timestamp to a date, not a calendar date back to a timestamp.

Epoch converter FAQ

What is Unix or epoch time?

Epoch time counts seconds since 1 January 1970 00:00:00 UTC. It is a timezone-neutral representation commonly used in APIs and databases.

How can I convert between seconds and milliseconds?

Divide millisecond values by 1,000 to obtain seconds, or multiply seconds by 1,000 for millisecond precision. The converter accepts either format when you select the matching unit.

Why do I see different results for local time and UTC?

Local output applies your system's timezone and daylight-saving adjustments, while UTC shows the underlying absolute reference used in distributed systems.

What is the Year 2038 problem?

Systems that store epoch time as a 32-bit signed integer will overflow on 19 January 2038. Modern applications use 64-bit values, but legacy software may still need remediation.

Does the converter send my timestamps to a server?

No. HashyTools performs all conversions in your browser so sensitive dates never leave your device.

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Run the AES interoperability guide or read how these tools are checked.