Epoch/Unix Time Converter
Convert Unix epoch timestamps to human-readable dates and back. Live current epoch clock, auto-detect seconds vs milliseconds, output in UTC, local time, ISO 8601, and relative time. Free, instant, and private.
Epoch to Date
Date to Epoch
Quick Timestamps
Key Features
Live Epoch Clock
Watch the current Unix timestamp tick upward in real time, displayed in both seconds and milliseconds. The live clock gives you an instant reference point for debugging, logging, and verifying timestamp values against the current moment without needing to open a terminal or write any code.
Auto-Detect Seconds & Milliseconds
Paste any timestamp and the converter automatically determines whether it is in seconds or milliseconds based on its digit count. You see the result in both formats, along with UTC, local time, ISO 8601, and a human-friendly relative time like "3 hours ago" or "in 2 days." No manual selection needed.
Bidirectional Conversion
Convert in either direction — from an epoch timestamp to a human-readable date, or from a date and time picker back to an epoch value. The date-to-epoch converter outputs seconds and milliseconds simultaneously, making it easy to copy the format your application requires.
Quick Timestamp Shortcuts
Generate commonly needed timestamps with a single click. Buttons for "Now," "+1 Hour," "+1 Day," "+1 Week," "Start of Today," and "Start of Year" let you produce reference timestamps instantly. Each shortcut displays the full date alongside the seconds and milliseconds values.
How Epoch Converter Works
- View the live clock — The top of the tool displays the current Unix epoch time updating every second, shown in both seconds and milliseconds. Use it as an instant reference while working with timestamps in your code or logs.
- Convert epoch to date — Paste a numeric timestamp into the "Epoch to Date" input field and click Convert. The tool automatically detects whether the value is in seconds (10 digits) or milliseconds (13 digits) and displays the result in UTC, your local timezone, ISO 8601 format, and as a relative time description.
- Convert date to epoch — Use the date and time pickers in the "Date to Epoch" section. Select any date and time, then click Convert to see the corresponding epoch value in both seconds and milliseconds. Click "Now" to instantly populate the current date and time.
- Use quick shortcuts — Click any quick timestamp button to generate a commonly needed value. Each shortcut shows the full date alongside the epoch in seconds and milliseconds, ready to copy into your application, database query, or configuration file.
JavaScript's Date.now() returns milliseconds since epoch, while Unix timestamps in most server languages (Python, PHP, Ruby) use seconds. Forgetting to divide by 1000 is the most common cause of dates displaying as the year 53000+ in cross-platform applications.
The Unix epoch (January 1, 1970) is not arbitrary — it was chosen because Unix was being developed around that time and needed a recent, round reference point. Timestamps before this date are negative numbers, which some systems handle incorrectly or reject entirely.
Understanding Unix Epoch Time
Unix epoch time, also called POSIX time or Unix time, is a system for tracking time as a running count of seconds since a fixed reference point: midnight on January 1, 1970, Coordinated Universal Time (UTC). This reference moment is known simply as "the epoch." Every second that passes increments the counter by one, making the timestamp a single, unambiguous integer that carries no timezone or daylight saving information. Because of its simplicity, epoch time has become the universal lingua franca for representing points in time across operating systems, programming languages, databases, and network protocols.
The original choice of January 1, 1970, was a pragmatic decision by the engineers who built the early Unix operating system at Bell Labs. When they redesigned Unix around 1971, they needed a compact, fixed reference for their internal clock. The 1970 date provided a recent, round-numbered starting point that allowed a 32-bit signed integer to represent dates spanning roughly 68 years into the past and 68 years into the future. There is no astronomical, religious, or political significance behind the choice — it was purely a matter of engineering convenience.
One well-known limitation of the original 32-bit representation is the Year 2038 problem, commonly abbreviated as Y2K38. A signed 32-bit integer can hold a maximum value of 2,147,483,647, which maps to Tuesday, January 19, 2038, at 03:14:07 UTC. One second later the integer overflows, wrapping around to a large negative number that the system interprets as a date in December 1901. While this is analogous to the Year 2000 bug, the fix is more straightforward: transitioning to a 64-bit integer pushes the overflow date to over 292 billion years into the future. Most modern operating systems, including Linux, macOS, and Windows, have already completed this migration, but older embedded devices, industrial controllers, and legacy database schemas may still be at risk.
In day-to-day programming, epoch timestamps appear everywhere. JavaScript represents time in milliseconds since the epoch — calling Date.now() returns a 13-digit number. Python's time.time() returns a floating-point number of seconds, while its datetime module can convert between epoch values and structured date objects. Java and Kotlin use System.currentTimeMillis() for milliseconds. PHP's time() function and MySQL's UNIX_TIMESTAMP() return seconds. Understanding which unit a given API or database column uses — seconds versus milliseconds — is essential to avoid bugs where dates appear either thousands of years in the future or stuck in January 1970.
Not all computing platforms share the same epoch. Classic Mac OS used January 1, 1904. Microsoft Windows FILETIME counts 100-nanosecond intervals from January 1, 1601. The Network Time Protocol (NTP) uses January 1, 1900. Apple's Cocoa framework and Swift language reference January 1, 2001. GPS time began on January 6, 1980, and does not account for leap seconds, creating a growing offset from UTC. Despite these variations, the Unix epoch remains the dominant standard on the web and in server-side development. Converting between epoch systems is simply a matter of adding or subtracting a fixed offset, making cross-platform interoperability reliable once you know which epoch each system uses.
When to Use This
Backend Developer Debugging API Timestamps
A developer receives a 1711814400 value in an API response and needs to verify it represents the expected date. They paste the timestamp to confirm it decodes to March 31, 2024 — catching that the API is returning last year's data instead of current results.
Data Analyst Converting Database Timestamps
An analyst exporting data from PostgreSQL finds timestamps stored as epoch integers. They need to convert thousands of values to human-readable dates for a report. The converter helps verify the format (seconds vs. milliseconds) before writing the batch conversion query.
DevOps Engineer Investigating Log Entries
An engineer triaging a production incident needs to correlate log entries from different systems that use Unix timestamps. Converting timestamps to local time helps build an accurate incident timeline across services running in different regions.
Your Questions Answered
How do I convert a Unix timestamp to a human-readable date?
Paste the numeric timestamp into the "Epoch to Date" input field and click Convert. The tool automatically detects whether the value is in seconds (10 digits) or milliseconds (13 digits) and displays the result in four formats: UTC, your local timezone, ISO 8601, and relative time (e.g., "3 days ago"). For example, entering 1700000000 shows November 14, 2023, at 22:13:20 UTC. All conversions run in your browser — no data is sent to any server.
How do I tell if a timestamp is in seconds or milliseconds?
Count the digits. A seconds-based Unix timestamp for current dates is 10 digits (e.g., 1700000000), while a millisecond timestamp is 13 digits (e.g., 1700000000000). This converter detects the format automatically. If you are working with code, JavaScript's Date.now() and Java's System.currentTimeMillis() return milliseconds, while Python's time.time(), PHP's time(), and most SQL UNIX_TIMESTAMP() functions return seconds. To convert between them, multiply seconds by 1,000 or divide milliseconds by 1,000.
How do I convert a specific date and time to a Unix timestamp?
Use the "Date to Epoch" section. Select any date and time using the pickers, then click Convert to see the corresponding epoch value in both seconds and milliseconds. Click the "Now" button to instantly populate the current date and time. The resulting values are ready to paste into your application, database query, API request, or configuration file.
Can I use negative timestamps for dates before 1970?
Yes. Negative epoch timestamps represent dates before January 1, 1970, 00:00:00 UTC. The timestamp -86400 means December 31, 1969 (one day before the epoch). Most programming languages handle negative values correctly — JavaScript's Date object, Python's datetime module, and Java's Instant class all accept them. The practical lower limit depends on whether the system uses 32-bit integers (back to December 1901) or 64-bit integers (billions of years).
Will my system be affected by the Year 2038 problem?
The Y2K38 problem affects systems storing Unix time as a 32-bit signed integer, which overflows on January 19, 2038, at 03:14:07 UTC. Most modern operating systems, programming languages, and browsers have migrated to 64-bit timestamps (good for 292 billion years). However, legacy embedded systems, older database columns (like MySQL's TIMESTAMP type before 8.0.28), IoT firmware, and some file format headers may still be vulnerable. Use this converter to test timestamps near the 2,147,483,647 boundary and verify your applications handle them correctly.
How do I get the current epoch time in different programming languages?
JavaScript: Date.now() returns milliseconds; Math.floor(Date.now() / 1000) for seconds. Python: time.time() returns seconds as a float. PHP: time() returns seconds. Java/Kotlin: System.currentTimeMillis() returns milliseconds. Ruby: Time.now.to_i returns seconds. In SQL, MySQL uses UNIX_TIMESTAMP() and PostgreSQL uses EXTRACT(EPOCH FROM NOW()). The live clock at the top of this tool shows the current epoch updating every second for quick reference.
The Year 2038 Problem
The Year 2038 Problem, sometimes called the "Unix Millennium Bug" or Y2K38, is a critical computing limitation that will cause many systems to malfunction on January 19, 2038. It stems from the way early Unix systems chose to represent time.
What Happens
At this exact moment, the 32-bit signed integer rolls over from its maximum positive value to its minimum negative value (-2,147,483,648), which the system interprets as December 13, 1901. Any software relying on 32-bit time_t will jump backward by 137 years.
Why It Matters
While desktop operating systems and modern programming languages have largely migrated to 64-bit timestamps (which will not overflow for another 292 billion years), the 32-bit time_t format persists in billions of embedded systems, legacy databases, file format headers, and IoT devices. Industrial controllers, automotive systems, medical equipment, and network infrastructure firmware often use 32-bit timestamps because they were designed decades ago and are difficult or impossible to update. Even some modern systems inadvertently create 32-bit timestamps through database column types, protocol specifications, or serialization formats inherited from older codebases.
How It Is Being Solved
Developers should audit any system that stores or processes Unix timestamps to verify it uses 64-bit integers. Use this converter to test timestamps near the 2,147,483,647 boundary and confirm your applications handle them correctly.