Free browser tool

Timecode calculator

Add or subtract timecodes. Convert a duration to frames, or turn a frame count into timecode.

Calculations stay in your browser. Your inputs are not uploaded.

OperationFrame rate

Use drop-frame labels, available at 29.97 and 59.94 fps

All inputs use the selected rate. Changing the rate reinterprets the labels; it does not convert footage between rates.

First timecodeSecond timecode to add

Use HH:MM:SS:FF. Hours may exceed 23. Minutes and seconds must be 00–59. An optional minus sign represents a negative duration.

Result as timecode

How to calculate timecode

Choose your project's frame rate, then select an operation. Enter hours, minutes, seconds and frames. At 24 fps, adding 00:00:59:23 and 00:00:00:01 gives 00:01:00:00. Subtraction uses the first value minus the second and can return a negative duration.

A frame count is a duration from zero. This tool does not include both endpoints of an in/out range, infer a project's starting timecode, or convert one frame rate to another.

Timecode labels and elapsed time

23.976, 29.97 and 59.94 use the exact rates 24000/1001, 30000/1001 and 60000/1001 frames per second. Non-drop-frame labels count at 24, 30 or 60 frames per labeled second. For example, 01:00:00:00 at 29.97 non-drop-frame contains 108,000 frames and lasts 3,603.6 seconds. The elapsed-seconds result makes that difference visible.

What does drop-frame mean?

Drop-frame skips timecode numbers, not video frames. At 29.97 fps it skips frame labels 00 and 01 at the beginning of every minute except each tenth minute. At 59.94 fps it skips labels 00 through 03. Use a semicolon before the frame field. The calculator rejects skipped labels such as 00:01:00;00 and accepts 00:10:00;00.

Drop-frame closely tracks clock time, but the exact frame rate still determines elapsed seconds. See Apple's timecode documentation and frame-rate guidance.

Working with markers?

Use the Marker CSV and timestamp converter for whole-second marker lists, or make YouTube timestamp links. These tools have their own formats; frame timecodes cannot be pasted into a whole-second list unchanged.

Try Marker on TestFlight to capture moments while you work. Check TestFlight for current beta availability and supported devices.