How this calculator works
Every full second holds one frame rate worth of frames, so the hours, minutes and seconds are converted to seconds, multiplied by the rate and added to the frame number. At 24 frames per second, 00:02:30:01 is 150 full seconds plus one frame, which is 150 x 24 + 1 = 3601 frames. The frame field must be smaller than the rate, because a value equal to or larger than the rate would already be the next second. The extra output converts the count into 35 mm four-perforation film feet, where 16 frames make one foot.
Formula
total frames = (hours x 3600 + minutes x 60 + seconds) x frame rate + frames. total seconds = hours x 3600 + minutes x 60 + seconds + frames / frame rate. 35 mm four-perforation feet = total frames / 16.
Worked example
The timecode 00:02:30:01 at 24 frames per second is 2 minutes 30 seconds and one frame. That is 150 seconds, or 150 x 24 = 3600 frames, plus one, giving 3601 frames and 150.0417 seconds. The same timecode at 25 frames per second is 3751 frames, because each second holds one more frame. One hour at 25 frames per second is 90,000 frames, and at 24 frames per second it is 86,400 frames.
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Frequently asked questions
Why must the frame field be below the frame rate?
The frame field counts the frames within one second, starting at zero, so at 24 frames per second it runs from 0 to 23. A value of 24 is already the first frame of the next second and should be written by increasing the seconds.
How do I convert drop-frame timecode?
Drop-frame labels skip frame numbers so the clock stays aligned with real time. To get the true frame count you must remove the skipped labels, which this integer-rate page does not attempt. Use a drop-frame-aware tool for 29.97 or 59.94 sequences.
Does timecode start at zero or one?
It starts at 00:00:00:00 for the first frame in the usual convention. Some broadcast systems start at 01:00:00:00 so that negative counts have room, which adds a fixed offset.
Why show film feet?
Film cameras and labs still measure negative in feet. At 16 frames per foot for 35 mm four-perforation film, a frame count converts directly, which is handy when comparing a film scan with a modern frame count.