Timecode Calculator: Frames, Timecode and Drop-Frame
Timecode counts frames as hours:minutes:seconds:frames. At whole frame rates (24, 25, 30) it is just frames divided by the rate. At 29.97 fps, which is really 30000/1001, plain timecode drifts from the clock by about 3.6 seconds an hour, so drop-frame timecode skips frame numbers 00 and 01 at the start of every minute except every tenth. No picture frames are removed, only numbers. This calculator converts both ways.
Timecode calculator
Pick the frame rate and direction. Results update as you type and the numbers are saved in the page address. Nothing leaves your browser. Timecode starts at 00:00:00:00 and wraps at 24 hours.
How the timecode calculator works
Each frame gets a number. At a whole rate, the timecode is the frame count split into hours, minutes, seconds and frames. For 29.97 drop-frame the counter first adds back the skipped numbers (2 per minute, none at every tenth minute) and then splits as usual. Real elapsed time uses the exact rate, 30000/1001 for 29.97.
nominal = 24, 25, 30, 50 or 60 (frames per timecode second) non-drop frames = ((HH × 60 + MM) × 60 + SS) × nominal + FF drop-frame frames = non-drop frames − D × (total minutes − floor(total minutes ÷ 10)) real seconds = frames × 1001 ÷ 30000 (at 29.97; 1001 ÷ 24000 at 23.976; 1001 ÷ 60000 at 59.94)
- D
- skipped numbers per minute: 2 at 29.97 drop-frame, 4 at 59.94 drop-frame (unconfirmed)
- total minutes
- HH × 60 + MM
Worked example
Given: 29.97 fps drop-frame; timecode 01:00:00;00.
- Non-drop count:
(1 × 60 + 0) × 60 × 30 = 108,000 numbers - Skipped numbers:
2 × (60 − floor(60 ÷ 10)) = 2 × 54 = 108 - Frames:
108,000 − 108 = 107,892 - Real time:
107,892 × 1001 ÷ 30,000 = 3,599.996 s, within 4 ms of one clock hour
Answer: 01:00:00;00 at 29.97 drop-frame is frame 107,892, about one real hour. The same 107,892 frames at non-drop show 00:59:56:12.
Exact frame rates used
| Label | Timecode frames per second | Exact rate | Skipped per minute |
|---|---|---|---|
| 23.976 fps | 24 | 24000/1001 | none |
| 24 fps | 24 | 24 | none |
| 25 fps | 25 | 25 | none |
| 29.97 fps non-drop | 30 | 30000/1001 | none |
| 29.97 fps drop-frame | 30 | 30000/1001 | 2 |
| 30 fps | 30 | 30 | none |
| 50 fps | 50 | 50 | none |
| 59.94 fps non-drop | 60 | 60000/1001 | none |
| 59.94 fps drop-frame | 60 | 60000/1001 | 4 |
| 60 fps | 60 | 60 | none |
Sources 1 and 2. The 24000/1001 and 30000/1001 fractions are listed by Apple; 60000/1001 and the 59.94 drop-frame count of 4 are unconfirmed against a manufacturer page.
Assumptions and limits
- Drop-frame is offered at 29.97 and 59.94 only. The 59.94 rule (4 numbers per minute) is unconfirmed here.
- Timecode starts at 00:00:00:00 and wraps at 24 hours; a start offset such as 01:00:00:00 is not applied.
- Real elapsed time is the media duration at the exact rate. A device's clock may differ.
- Interlaced field timecode, 30 fps drop-frame and 25 fps variants are not covered.
- Check how your editor counts: some show non-drop and drop-frame timecode with different separators (a semicolon for drop-frame is common).
Frequently asked questions
What is drop-frame timecode?
A timecode counting method for 29.97 fps video. Certain frame numbers are skipped at specific intervals, except every tenth minute, so the timecode stays close to real clock time. RØDE describes the skipped numbers as typically 0 and 1, and Apple describes drop frame as a format that prioritises elapsed time over frames elapsed. Apple also notes that using it does not mean your video has dropped frames; it only changes the timecode display. A semicolon before the frame count, as in 00:01:00;02, usually marks it.
Why does 29.97 fps exist?
The exact rate is 30000/1001 frames per second, slightly less than 30. Apple's technical note QA1447 lists 29.97 as 30000/1001 and 23.976 as 24000/1001. This calculator uses those fractions to work out real elapsed time.
How far does non-drop 29.97 drift from the clock?
Timecode at non-drop 29.97 counts 30 frames per second but the video plays 29.97, so one hour of timecode (108,000 frames) takes 108,000 × 1001 ÷ 30,000 = 3,603.6 seconds, 3.6 seconds longer than a clock hour. Drop-frame timecode removes 108 numbers per hour to correct that. Try 108,000 frames at both settings above.
Which frame numbers are skipped?
At 29.97 drop-frame, 00 and 01 do not exist at the start of each minute, so 00:00:59;29 is followed by 00:01:00;02. Every tenth minute (10, 20, 30...) keeps all frame numbers. The calculator rejects a timecode that falls in a skipped number.
Does 59.94 drop-frame work the same way?
The usual practice is to skip four numbers per minute instead of two. That rule is unconfirmed here: we did not find a manufacturer page stating it, so check your editor before relying on 59.94 drop-frame values. The 29.97 drop-frame rule is the one cited above.
Is there a drop-frame mode for 23.976 or 24 fps?
This calculator does not offer one. 23.976 and the whole-number rates use plain timecode, and we found no source for a standard drop-frame variant of them.
Does this recommend any software?
No. It is arithmetic only.
Sources
- Apple, Technical Q&A QA1447: Final Cut Pro X preferred video media time scales and sample durations (23.976 and 29.97 as 24000/1001 and 30000/1001) (developer.apple.com) Accessed 2026-11-13.
- RØDE Help Centre: the difference between 29.97 and 29.97 DF (help.rode.com) Accessed 2026-11-13.
- Apple Compressor User Guide: drop frame timecode (support.apple.com) Accessed 2026-11-13.