Unix Timestamp Converter — Epoch Time to Date and Back
Paste any epoch, get UTC, local, ISO 8601, and relative time instantly
Unix timestamps power virtually every backend system, API, and database — but a raw number like 1735689600 tells a developer nothing at a glance. This converter transforms epoch times into every useful format in one step. Paste a timestamp in seconds or milliseconds and the tool auto-detects the precision, then shows you UTC time, your local timezone, ISO 8601, a relative description ("3 days ago"), and both second and millisecond equivalents side by side. Going the other direction is just as easy — use the date-time picker to select any moment and get its Unix timestamp. Hit "Use now" to convert the exact current instant.
How to Convert Unix Timestamps
Paste a timestamp or pick a date — all formats appear instantly with no button click.
Paste a Unix timestamp
Type or paste your Unix timestamp into the input field. The tool automatically detects whether it is in seconds (10 digits, e.g. 1700000000) or milliseconds (13 digits, e.g. 1700000000000). Click Use now to fill the current timestamp and see what today looks like in each format.
Read all the output formats
Six output rows appear simultaneously: UTC (universal reference time), Local (your browser timezone), ISO 8601 (international standard format such as 2023-11-14T22:13:20Z), Relative (human-friendly description such as 6 months ago), Unix seconds, and Unix milliseconds. Each row has a copy button.
Convert a date back to epoch
Use the date and time picker in the lower section to select any calendar date and time. The corresponding Unix timestamp in seconds and milliseconds appears instantly, ready to copy into your code, database query, or API payload.
Features
Auto-detects seconds (10-digit) vs milliseconds (13-digit) timestamps
Shows UTC, local timezone, ISO 8601, and relative time simultaneously
Use now button converts the current moment instantly
Date-time picker for date-to-epoch conversion
Copy button on every output row
Works for any timestamp from 1970 to 2038 and beyond
Runs entirely in your browser — no server request made
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Frequently Asked Questions
What is a Unix timestamp?
A Unix timestamp is the number of seconds (or milliseconds) that have elapsed since the Unix epoch — 00:00:00 UTC on January 1, 1970. It is a timezone-independent, universal representation of a specific moment in time and is widely used in databases, APIs, log files, and programming languages.
How do I tell if a timestamp is in seconds or milliseconds?
A 10-digit timestamp is in seconds (covers dates from 2001 to 2286). A 13-digit timestamp is in milliseconds (covers the same range at higher precision). The tool detects this automatically. If you receive a 10-digit number starting with 1, it is almost certainly a seconds-precision Unix timestamp from 2001 onwards.
How do I get the current Unix timestamp in JavaScript?
Use Date.now() for milliseconds or Math.floor(Date.now() / 1000) for seconds. In Node.js you can also use process.hrtime() for nanosecond precision.
Why do timestamps sometimes differ by hours between systems?
Unix timestamps are UTC-based and timezone-neutral. Differences usually appear when one system stores or displays the timestamp in local time rather than UTC. Always store timestamps as UTC and convert to local time only for display.
What is the Unix timestamp for midnight on January 1, 2025?
Midnight UTC on January 1, 2025 is Unix timestamp 1735689600 (seconds). You can verify this by entering that number in the converter above — it should display 2025-01-01T00:00:00Z in ISO 8601 format.