Free calculator
Timecode Calculator
Add and subtract timecode, multiply or divide a duration, and convert timecode to frames or frames to timecode. Everything is counted in whole frames, and 29.97 and 59.94 drop-frame follow the SMPTE counting rule.
Free, no sign-up. Runs in your browser.
This web tool counts drop-frame timecode correctly when it converts timecode to frames. Save, share and get the Pro tools in the app.
How it works
frames = (HH × 3600 + MM × 60 + SS) × timecode rate + FFThe timecode rate is the whole number timecode counts in: 24 for 23.976, 30 for 29.97, 60 for 59.94. 23.976 timecode labels 24 frames per timecode second, which is why an hour of it runs 3,603.6 real seconds.
frames = non-drop count − d × (M − ⌊M ÷ 10⌋)M is total minutes (HH × 60 + MM) and d is the labels skipped per minute: 2 at 29.97 DF, 4 at 59.94 DF. Drop-frame skips frame numbers, never frames: ;00 and ;01 are left out at the start of every minute except minutes 00, 10, 20, 30, 40 and 50.
TC₁ ± TC₂ = label(frames₁ ± frames₂)Every operation converts to frames, does the arithmetic on whole frames (multiply and divide round to the nearest frame), then writes the frame number back as a label. Duration in seconds is frames ÷ the actual frame rate.
Time of day or a running total
Time-of-day timecode runs from 00:00:00:00 to 23:59:59:FF and wraps at midnight, the way a timecode generator does: 23:00:00:00 + 02:00:00:00 is 01:00:00:00. Choose Keep counting to add up a running time past 24 hours instead (25:00:00:00). Timecode to frames never wraps: it counts the frames from the start you give it.
Worked example
Adding two timecodes at 23.976 fps
- 01:23:45:12 → (3600 + 1380 + 45) × 24 + 12 = 120,612 frames
- 00:15:30:08 → (900 + 30) × 24 + 8 = 22,328 frames
- 120,612 + 22,328 = 142,940 frames
- 142,940 ÷ 24 = 5,955 s remainder 20 → 01:39:15:20
- Real duration: 142,940 ÷ 23.976 = 5,961.80 s
01:23:45:12 + 00:15:30:08 = 01:39:15:20 (142,940 frames)
Quick reference
Timecode to frames: 01:00:00:00
| Frame rate | Frames in one hour of timecode |
|---|---|
| 23.976 NDF | 86,400 |
| 24 | 86,400 |
| 25 | 90,000 |
| 29.97 DF | 107,892 |
| 30 | 108,000 |
Frames to time: 240 frames
| Frame rate | Timecode | Seconds |
|---|---|---|
| 24 | 00:00:10:00 | 10 |
| 30 | 00:00:08:00 | 8 |
| 60 | 00:00:04:00 | 4 |
Drop-frame reference points at 29.97 DF
| Timecode | Frame number |
|---|---|
| 00:00:59;29 | 1,799 |
| 00:01:00;02 | 1,800 |
| 00:10:00;00 | 17,982 |
| 01:00:00;00 | 107,892 |
| 23:59:59;29 | 2,589,407 |
Save, share and get the Pro tools in the CineMath app
CineMath is a free download for iPhone, iPad and Mac, with this calculator built in. In version 1.3, coming soon to the App Store, CineMath Professional saves calculations to your history, shares them as links, and adds the Camera Database and Data Planning.
Questions
How do I convert timecode to frames?
Multiply hours by 3,600 and minutes by 60, add the seconds, multiply by the timecode rate and add the frames. 01:00:00:00 at 24 fps is 3,600 × 24 = 86,400 frames. At 23.976 the timecode rate is 24, so the answer is the same.
How many frames are in an hour of 29.97 drop-frame timecode?
107,892. Non-drop 29.97 counts 108,000 frames in an hour of timecode; drop-frame skips 2 frame numbers in 54 of the 60 minutes, and 108,000 − 108 = 107,892. At 29.97 fps that is 3,600.0 real seconds.
How do I convert frames to timecode?
Divide the frame count by the timecode rate: the whole number is seconds and the remainder is frames. Then split the seconds into hours and minutes. 1,440 frames at 24 fps is 60 seconds, 00:01:00:00. For drop-frame, renumber past the skipped labels: frame 1,800 at 29.97 DF is 00:01:00;02.
What is the difference between drop-frame and non-drop-frame?
Both run at 29.97 frames per second and drop no pictures. Non-drop numbers every frame, so its timecode falls 3.6 seconds behind the clock every hour. Drop-frame skips some frame numbers so an hour of timecode is an hour of real time. Drop-frame is written with a semicolon before the frames: 01:00:00;00.
How do I add two timecodes together?
Convert both to frames at the same rate, add the frame counts, and convert back. 01:23:45:12 + 00:15:30:08 at 23.976 is 120,612 + 22,328 = 142,940 frames, which is 01:39:15:20.
Why is an hour of 23.976 timecode longer than an hour?
23.976 timecode counts 24 frames per timecode second, but the frames play slightly slower than 24 per second. 86,400 frames ÷ 23.976 = 3,603.6 seconds, so an hour of 23.976 timecode runs 3.6 seconds longer than a clock hour. There is no drop-frame timecode at 23.976.