Free to use. No sign-up required. All calculations run on your device.
Add and subtract in frames
Total frames = sum of each signed segment’s frame count. The timecode total is generated from that final count, not by adding the printed digits.
Worked example
At 24 fps, 00:10:00:00 + 00:02:30:00 = 00:12:30:00 = 18,000 frames = 750 seconds. Subtract 00:00:00:12 to get 00:12:29:12, or 17,988 frames.
Assumptions and limits
All segments use the same selected rate. Durations can be negative or longer than 24 hours. This is duration arithmetic: adding two DF clock labels does not preserve their wall-clock appearance. Up to 50 segments; no automatic saving.
All modes accept a signed timecode or compact digits, right-aligned into hours, minutes, seconds and frames. For example, 1020304 becomes 01:02:03:04. Up to 11 digits supports extended hours; minutes and seconds stay below 60, and the frame field stays below nominal fps. A semicolon requires a DF frame rate. Frame counts are limited to ±1 trillion.
Nominal labels and actual frame rate
A timecode’s frame field uses the nominal integer rate. Actual seconds use the exact rate below. The labels “23.976,” “29.97” and “59.94” are shorthand, not rounded decimal divisors. NDF means non-drop-frame.
On a narrow screen, scroll the table sideways to read all three columns.
| Rate shown | Actual fps | Labels |
|---|---|---|
| 23.976 | 24000/1001 | 24, NDF |
| 24, 25, 30 | 24, 25, 30 | Same as fps |
| 29.97 | 30000/1001 | 30, DF or NDF |
| 48, 50, 60 | 48, 50, 60 | Same as fps |
| 59.94 | 60000/1001 | 60, DF or NDF |
Check the label convention first
Match the source project’s rate and DF/NDF setting before calculating. These tools do not inspect media, infer the rate from your footage, or convert a file. Seconds are displayed to six decimals; frame arithmetic retains whole frames. Check final delivery settings in your editing system.
For the drop-frame rule and independently reproducible equations, see David Heidelberger’s drop-frame timecode explanation and SMPTE standards. Our examples above include integer hand calculations so you can check them without an account or upload.