Timecode Calculator
Add or subtract two video timecodes at common frame rates, including 29.97 drop-frame.
Resulting timecode
01:00:30;15
- Total frames
- 108,807
- Real running time
- 1:00:31
The result is 01:00:30;15, which is 108,807 frames.
Calculation breakdown
| Step | Formula | Result |
|---|---|---|
| Frames | 107,892 frames and 915 frames combined | 108,807 |
| Real running time | 108,807 frames ÷ the true frame rate | 1:00:31 |
How it works
Choose the frame rate, then type the two timecodes. A semicolon, colon or period all work between fields.
Worked example
At 29.97 drop-frame, 01:00:00;00 plus 00:00:30;15:
- First: 60 minutes × 1,800 = 108,000 − 2 × (60 − 6) = 107,892 frames
- Second: 30 × 30 + 15 = 915 frames (no minute boundary crossed)
- Total: 108,807 frames, which is 01:00:30;15 in drop-frame
Real running time
The calculator also shows real running time, which uses the true rate (for example 30 ÷ 1.001).
Sources
Frequently asked questions
How do you add timecodes?
Convert each one to a frame count, add the counts, then convert back. Frames are (hours × 3600 + minutes × 60 + seconds) × frame rate + frames. At 25 fps, 00:00:10:20 plus 00:00:05:10 is 00:00:16:05.
What is drop-frame timecode?
Drop-frame timecode skips frame numbers 0 and 1 at the start of every minute, except every tenth minute. No video frames are removed, only numbers. This keeps 29.97 fps timecode in step with the clock.
Why does 29.97 fps need drop-frame at all?
The real rate is 30 ÷ 1.001 frames per second, so counting 30 numbers a second runs 3.6 seconds long over an hour. Dropping 18 numbers every ten minutes fixes almost all of that.
Why are some drop-frame timecodes rejected?
Numbers such as 00:01:00;00 and 00:01:00;01 never appear, because they are the skipped ones. The calculator only accepts timecodes that exist.
Is 59.94 drop-frame supported?
Not yet. This tool covers drop-frame at 29.97 fps, where the rule is verified. The 23.976, 29.97 and 59.94 rates work as non-drop.
Check the result in your editing software before delivering a project, because tools can differ in how they display drop-frame.