Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa. Supports seconds, milliseconds, UTC, ISO 8601, and relative time.
Timestamp → Date
Date → Timestamp
Free Online Unix Timestamp Converter
Unix timestamps (also known as epoch time or POSIX time) count the number of seconds since January 1, 1970 at 00:00:00 UTC. This is the universal time format used by computers, servers, databases, and APIs worldwide. SmarterSources' Timestamp Converter makes it easy to convert between Unix timestamps and human-readable dates. Everything runs in your browser — no data is sent to any server.
Timestamp to Date
Enter a Unix timestamp and instantly see the corresponding local date and time, UTC date and time, ISO 8601 format, relative time (like "3 hours ago"), day of the week, and ISO week number. The tool auto-detects whether your input is in seconds or milliseconds — if the value is greater than 10 trillion, it is treated as milliseconds.
Date to Timestamp
Select a date and time using the date picker and time inputs, and the tool converts it to Unix seconds, Unix milliseconds, and ISO 8601 format. The conversion uses your local timezone, which is displayed for reference.
Live Current Timestamp
The live counter at the top of the tool shows the current Unix timestamp, updating every second. This is useful for logging, debugging, or quickly grabbing the current epoch time.
Frequently Asked Questions
What is a Unix timestamp?
A Unix timestamp (also called epoch time) is the number of seconds that have elapsed since January 1, 1970 at 00:00:00 UTC. It is a simple, timezone-independent way to represent a specific moment in time. Most programming languages and databases use Unix timestamps internally.
What is the difference between seconds and milliseconds?
A Unix timestamp in seconds is typically a 10-digit number (e.g., 1700000000). In milliseconds, it is a 13-digit number (e.g., 1700000000000). JavaScript's Date.now() returns milliseconds, while many server-side languages and Unix commands use seconds. This tool supports both formats.
What is the Year 2038 problem?
Many older systems store Unix timestamps as 32-bit signed integers, which can only represent dates up to January 19, 2038 at 03:14:07 UTC. After that, the value overflows and wraps around to a negative number, potentially causing errors. Modern systems use 64-bit integers, which extend the range to billions of years into the future.
What is ISO 8601?
ISO 8601 is an international standard for representing dates and times as strings. The most common format is 2024-01-15T14:30:00.000Z, where T separates the date and time, and Z indicates UTC. It is the preferred format for APIs and data interchange because it is unambiguous and sorts correctly as text.
How is relative time calculated?
Relative time shows the difference between the timestamp and the current time in human-friendly terms like "3 hours ago" or "in 5 days." The tool calculates the absolute difference in seconds and converts it to the most appropriate unit (seconds, minutes, hours, days, months, or years).
Is my data private?
Yes. All conversions happen entirely in your browser using JavaScript. No data is sent to any server. SmarterSources does not collect or store any timestamps or dates you enter.