Epoch Time Calculator
Convert Unix and Linux epoch time to a date, and back again.
How do I convert a Unix timestamp to a date?
A Unix timestamp counts the seconds since 1 January 1970 UTC, so converting it adds those seconds to that moment.
Formula: Unix (epoch) time counts seconds since 1 January 1970 00:00:00 UTC. Milliseconds are the same count multiplied by 1,000.
Date and time (UTC)
Monday, January 1, 2024 at 00:00
- Unix seconds
- 1704067200
- Unix milliseconds
- 1704067200000
- ISO 8601 (UTC)
- 2024-01-01T00:00:00.000Z
- UTC
- Monday, January 1, 2024 at 00:00
- Relative to now
- 1035 days ago
- Offset applied
- 0 seconds
What this calculator does
Convert Unix timestamps in seconds or milliseconds to readable UTC dates, turn a date into epoch time, and add or subtract seconds, minutes, hours or days.
Use it to turn Convert, Unix timestamp, Timestamp unit, Date and time (UTC), and the other shown inputs into a checked result you can compare, copy, or rerun with different assumptions.
The page shows the formula, a numeric worked example, and the assumptions that affect this everyday calculation.
Inputs and what they mean
- Convert
- — choice value.
- Unix timestamp
- — Seconds or milliseconds since 1 January 1970 UTC..
- Timestamp unit
- — choice value.
- Date and time (UTC)
- — datetime-local value.
- Add or subtract
- — number value.
- Offset unit
- — choice value.
- Time format
- — 12 or 24 hour value.
How to use it
- Choose whether to convert a timestamp to a date or a date to a timestamp.
- Enter the value, and optionally add or subtract seconds, minutes, hours or days.
- Press Calculate to see seconds, milliseconds, ISO 8601 and readable UTC time.
Formula
Unix (epoch) time counts seconds since 1 January 1970 00:00:00 UTC. Milliseconds are the same count multiplied by 1,000.
Inputs used: Convert, Unix timestamp, Timestamp unit, Date and time (UTC), Add or subtract, Offset unit, Time format.
Edge handling: Unix timestamp is required.; Date and time (UTC) is required.; Date and time (UTC) must use a valid calendar date..
Worked example
Start of 2024
- Start with Convert: toDate, Unix timestamp: 1704067200, Timestamp unit: seconds, Add or subtract: 0, Offset unit: seconds, Time format: 24.
- Apply the method: Unix (epoch) time counts seconds since 1 January 1970 00:00:00 UTC. Milliseconds are the same count multiplied by 1,000.
- 1704067200 seconds is 1 January 2024 at 00:00 UTC.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
- Inputs outside the supported range are rejected rather than forced into a result.
- The result depends on the values you enter for this epoch time calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Common questions
How do I convert a Unix timestamp to a date?
A Unix timestamp counts the seconds since 1 January 1970 UTC, so converting it adds those seconds to that moment. Check the formula, example, and limitations on this page before using the result for a real everyday decision.
What is Unix or Linux time?
It is the number of seconds elapsed since 1 January 1970 00:00:00 UTC, the standard timestamp used by Linux, Unix and most programming languages. Check the formula, example, and limitations on this page before using the result for a real everyday decision.
Does it handle milliseconds?
Yes. Choose milliseconds as the unit, and every result also lists both seconds and milliseconds.
Are leap seconds included?
No. Unix time ignores leap seconds by definition, so every day counts exactly 86,400 seconds.
How do I use the Epoch Time Calculator?
Enter the required values for Convert, Unix timestamp, Timestamp unit, Date and time (UTC), Add or subtract, and the other fields shown. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
What formula does the Epoch Time Calculator use?
Unix (epoch) time counts seconds since 1 January 1970 00:00:00 UTC. Milliseconds are the same count multiplied by 1,000. The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.
Cite this page
Free Calculator. (n.d.). Epoch Time Calculator. https://freecalculator.tech/tools/epoch-time-calculator
"Epoch Time Calculator." Free Calculator, https://freecalculator.tech/tools/epoch-time-calculator.
Epoch Time Calculator — Free Calculator, https://freecalculator.tech/tools/epoch-time-calculator
Related tools
Calculate elapsed hours and minutes between two times, including overnight.