Check whether a Unix timestamp is in seconds or milliseconds

Use the converter to spot the classic 10-digit versus 13-digit unit mismatch before it creates off-by-years bugs.

Seconds and milliseconds often get mixed between APIs, databases, and frontend code. A fast conversion pass tells you whether the source value is even in the right unit.

Open the tool Expected result

How to use it

Step 1

Paste the raw numeric value

Avoid reformatting it first so you can inspect the source as it arrived.

Step 2

Compare both unit interpretations

See what happens if the value is treated as seconds and then as milliseconds.

Step 3

Match against business context

Check which interpretation fits the event date you expected.

Sample input

1711027200

Expected result

You quickly identify whether the bug is a unit mismatch before digging deeper into timezone display issues.

Common mistakes

Assuming every JavaScript timestamp is already in milliseconds.
Fixing the UI while the stored value is still wrong.
Ignoring surrounding log context that reveals the real event time.

Related workflows

Compare UTC and local time for the same event

Guide

Fix a milliseconds mismatch in logs or APIs

Guide

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ToolsDashboard

debug unix seconds timestamp

Check whether a Unix timestamp is in seconds or milliseconds

Use the converter to spot the classic 10-digit versus 13-digit unit mismatch before it creates off-by-years bugs.

Seconds and milliseconds often get mixed between APIs, databases, and frontend code. A fast conversion pass tells you whether the source value is even in the right unit.

Open the tool Expected result