Time From a Date Calculator

Inputs and units

• Reference date and time (UTC): Enter your value in the format and unit shown.
• Hours to add (negative subtracts): Enter your value in the format and unit shown.

Calculation method

Add the specified hours to a UTC reference timestamp.

Worked example

The example values are: Reference date and time (UTC) = 2026-01-01T12:00; Hours to add (negative subtracts) = 48

• Result (UTC): 2026-01-03T12:00:00.000Z

Assumptions and limitations

Uses UTC, so a 24-hour duration is exactly 24 elapsed hours.

Using your result

Select Calculate after changing inputs. Copy result copies the displayed output; Download result saves a text file. Reset returns the form to its example inputs. Calculations run in your browser.