Unix Timestamp Converter - Epoch Time Converter
How to Use the Unix Timestamp Converter
The tool displays the current Unix timestamp updating in real time at the top of the page. Enter a Unix timestamp (in seconds or milliseconds) to convert it to a human-readable date and time with timezone information. Alternatively, enter a date and time to get its Unix timestamp. Both conversion directions are instant.
What Is a Unix Timestamp
A Unix timestamp (also called epoch time or POSIX time) is a system for tracking time as a running total of seconds since January 1, 1970, 00:00:00 UTC. This reference point, known as the epoch, was established as the standard timekeeping method for Unix operating systems and has since become the universal standard for storing and comparing dates in computer systems.
Timestamps are timezone-independent by design. The value 1712400000 represents the same absolute moment in time regardless of whether you are in New York, London, or Tokyo. This property makes timestamps ideal for storing dates in databases and APIs where users may be in different time zones.
Seconds vs. Milliseconds
| Format | Digits | Example | Used By |
|---|---|---|---|
| Seconds | 10 | 1712400000 | PHP, Python, MySQL, PostgreSQL |
| Milliseconds | 13 | 1712400000000 | JavaScript, Java, Elasticsearch |
| Microseconds | 16 | 1712400000000000 | PostgreSQL, scientific computing |
| Nanoseconds | 19 | 1712400000000000000 | Go, high-precision systems |
This tool automatically detects whether your input is in seconds or milliseconds based on the number of digits.
Common Unix Timestamp Operations
Converting Timestamps in Code
Every programming language provides built-in functions for working with Unix timestamps:
| Language | Timestamp to Date | Date to Timestamp |
|---|---|---|
| JavaScript | new Date(ts * 1000) | Math.floor(Date.now() / 1000) |
| Python | datetime.fromtimestamp(ts) | int(time.time()) |
| PHP | date('Y-m-d', $ts) | time() |
| Java | Instant.ofEpochSecond(ts) | Instant.now().getEpochSecond() |
Timestamps in APIs and Databases
REST APIs commonly return dates as Unix timestamps because they are unambiguous, compact, and easy to compare. A timestamp like 1712400000 takes fewer bytes than an ISO 8601 string and eliminates timezone parsing issues on the client side.
Databases store timestamps efficiently as integers. Comparing two timestamps is a simple numeric comparison, making timestamp-indexed queries fast. Most databases also provide functions to convert between timestamps and human-readable date types.
The Year 2038 Problem
Systems that store Unix timestamps as 32-bit signed integers can only represent dates up to January 19, 2038, at 03:14:07 UTC. After this moment, the integer overflows and wraps to a negative number representing December 1901. This is known as the Y2K38 problem.
Modern 64-bit systems are not affected. They can represent timestamps far beyond any practical date. However, legacy embedded systems, older databases, and some file formats still use 32-bit timestamps. If you are designing new systems, always use 64-bit timestamp storage.
Timezone Considerations
Unix timestamps are always UTC. When displaying a timestamp to users, convert it to their local timezone. When accepting date input from users, convert from their local timezone to UTC before storing. This approach prevents the common bugs that arise from storing dates in local time.
For working with cron schedules that reference specific times, the Cron Expression Builder helps you define schedules with timezone awareness. If you need to convert the numeric representation of timestamps between number systems, the Number Base Converter handles decimal, hexadecimal, and binary conversions.
Related Tools
- Cron Expression Builder - Build time-based schedules that complement timestamps
- Number Base Converter - Convert timestamp values between number bases
- JSON / YAML / TOML Converter - Work with config files containing timestamp values
Frequently Asked Questions
What is the Unix epoch?
The Unix epoch is the reference point for Unix timestamps: January 1, 1970, at 00:00:00 UTC. All Unix timestamps are the number of seconds (or milliseconds) that have elapsed since this moment. It was chosen as the origin for the Unix operating system's internal clock.
What is the difference between seconds and milliseconds timestamps?
Unix timestamps in seconds are 10 digits long (e.g., 1712400000). Milliseconds timestamps are 13 digits long (e.g., 1712400000000) and provide more precision. JavaScript uses milliseconds (Date.now()), while most server-side languages and databases use seconds.
Will Unix timestamps run out of space (Year 2038 problem)?
Systems using a 32-bit signed integer for timestamps will overflow on January 19, 2038. Most modern systems have already moved to 64-bit timestamps, which will not overflow for billions of years. If you are building new systems, always use 64-bit time storage.
How do I get the current Unix timestamp?
This tool shows the current Unix timestamp in real time. In code, use Date.now()/1000 in JavaScript, time.time() in Python, System.currentTimeMillis()/1000 in Java, or the time() function in PHP. All return the current epoch time.