How to use the epoch time calculator
Prepare the values for this calculation
Convert between Unix epoch seconds and an ISO UTC date/time. Use the formula below to check that it answers your question. Read the input units before transferring figures from a statement, measurement or dataset.
Enter and check each input
- Conversion: choose Epoch seconds → UTC, UTC date/time → epoch seconds. Match this selection to the data you enter.
- Epoch seconds: replace the example with your text, keeping the format described in the input table.
- ISO UTC date/time: replace the example with your text, keeping the format described in the input table.
The input table gives a complete example. Keep units and time periods consistent across related fields.
Calculate and resolve any input error
Choose Calculate after entering the values. Changes also update the answer after a short pause. If an error appears, follow its message, correct the field and calculate again. Reset restores the example values.
Interpret the answer
Check Converted time first. With the unchanged example inputs, it is 1970-01-01T00:00:00.000Z. Interpret it using the formula and assumptions on this page.
Compare and keep a useful result
The result diagram shows the inputs, method and output. A numeric chart is shown only when the calculation supports a meaningful numeric relationship.
Use Copy result or Download CSV to keep the answer. Share tool shares the page address without placing your input values in the URL. Recheck inputs and assumptions before using the result for a decision.
Epoch Time Calculator formula
Unix time counts elapsed seconds from 1970-01-01T00:00:00Z.
Inputs and units
| Input | Format / range | Example |
|---|---|---|
| Conversion | Select an option | Epoch seconds → UTC |
| Epoch seconds | Number | 0 |
| ISO UTC date/time | Number | 1970-01-01T00:00:00Z |
Worked example
Using the example inputs above, the converted time is 1970-01-01T00:00:00.000Z.
- Converted time
- 1970-01-01T00:00:00.000Z
Results and assumptions
The output uses the converted time convention and formula shown above. Match the entered units and source assumptions when comparing results.
Fix an input or unexpected result
If your answer differs from the example, choose Reset and compare every field, including selected units and options. Check percentage versus decimal entry and whether values describe the same period. Round only the final displayed answer when reproducing the formula.
If a discrepancy remains, report the calculator issue with the page address, non-sensitive example inputs, actual result, expected result and a reference for your calculation.