A Complete Guide to the Unix Timestamp (Epoch Time)
Our Unix Timestamp Converter is an essential, secure tool for any developer, system administrator, or data analyst. It provides a fast, free, and precise way to convert a Unix timestamp (also known as Epoch time) into a human-readable date, and just as easily, convert any human-readable date back into its corresponding timestamp.
This tool is designed to handle all common use cases, from debugging log files and verifying API responses to generating timestamps for database entries. With one click, you can get the current timestamp, and our converter intelligently handles both 10-digit (second) and 13-digit (millisecond) timestamps. Most importantly, this is a 100% client-side tool. All conversions happen in your browser; your data is never sent to our servers.
Core Features
Convert from timestamp to date, or date to timestamp instantly.
Automatically handles both 10-digit (seconds) and 13-digit (milliseconds) epoch times.
A one-click button to get the current Unix timestamp in seconds.
What is a Unix Timestamp (Epoch Time)?
A Unix timestamp, or Epoch time, is a universal standard for tracking time. It is a single, simple integer that represents the total number of seconds that have passed since 00:00:00 Coordinated Universal Time (UTC) on Thursday, 1 January 1970. This specific moment in history is known as the Unix Epoch.
For example, a timestamp of `1728886400` refers to the exact moment 1,728,886,400 seconds have passed since the epoch. Our tool would instantly convert this to `Sun, 20 Oct 2024 14:13:20 GMT`.
This system is the backbone of timekeeping in almost every modern computing system. File systems (like on Linux, macOS, and Android) use timestamps to track when a file was created or modified. Databases (like MySQL, PostgreSQL) use them to log events. Programming languages (like Python, PHP, Java) have built-in functions to get and manipulate them. Its simplicity and lack of time zone ambiguity make it a universal standard.
Why Developers Must Use an Epoch Converter
While computers love timestamps, humans find them completely unreadable. A timestamp to date converter is an essential debugging tool.
- Debugging Log Files: Server logs (from Nginx, Apache, etc.) are filled with timestamps. When an error occurs, you need to paste that timestamp into a converter to know *when* it happened.
- Verifying API Responses: When you receive a JSON payload from an API, fields like `createdAt`, `updatedAt`, or `tokenExpires` are almost always epoch timestamps. This tool helps you instantly verify those dates.
- Checking Database Entries: When you look at a raw database table, the `created_at` column is often an integer. This converter helps you make sense of that data.
- Testing & Scheduling: If you need to write a test for "what happens in one hour?" or schedule a cron job, you can use our date to timestamp function to get the exact timestamp for a future event.
The Most Common Problem: Seconds vs. Milliseconds (10-Digit vs. 13-Digit)
A frequent source of bugs for developers is the confusion between timestamps in seconds and milliseconds.
- 10-Digit Timestamp (Seconds): This is the standard Unix timestamp. It is 10 digits long (e.g., `1678886400`). Systems like PHP (`time()`), Python (`time.time()`), and most SQL databases use timestamps in seconds.
- 13-Digit Timestamp (Milliseconds): This timestamp represents *milliseconds* since the epoch (e.g., `1678886400000`). This format is used almost exclusively by JavaScript, specifically with methods like
Date.now()ornew Date().getTime().
If you get a date in the year 54855, it's a classic sign you've mixed these up. You might have passed a millisecond timestamp to a function that expected seconds. Our epoch calculator intelligently detects the length and processes your number correctly, but it's crucial to know which format your system requires. To convert from JavaScript's milliseconds to a Unix timestamp, you must divide by 1000 and remove the decimal: Math.floor(Date.now() / 1000).
What is the "Year 2038 Problem"?
The Year 2038 Problem (or "Y2K38") refers to a critical bug in older, 32-bit computing systems. On these systems, the Unix timestamp was stored as a signed 32-bit integer. This type of integer can only hold values up to `2,147,483,647`.
At 03:14:07 UTC on Tuesday, 19 January 2038, the number of seconds since the epoch will exceed this limit. The integer will overflow and "wrap around," becoming a large negative number, which systems will interpret as a date in 1901. This could cause catastrophic failures in older infrastructure. Fortunately, all modern 64-bit systems (which are now standard) use a 64-bit integer, which has enough space to store timestamps for the next 292 billion years.
Related Tools in Our Toolbox
Timestamps are often found embedded in other data formats. If you're debugging, you'll likely find these tools just as useful:
- JWT Decoder: JSON Web Tokens rely on `exp` (expiration) and `iat` (issued at) claims, which are always Unix timestamps. Use our JWT Decoder to extract them, then paste them here to read them.
- JSON Formatter: The API responses you're checking for timestamps are almost always in JSON format. Use this tool to make them readable first.