RandoziTimecode Calculator
Add and subtract video timecodes, and convert between timecode, frame count and seconds at 24, 25, 30 or 29.97 fps — with drop-frame support.
Add or subtract
A + B
00:10:30:12
15,762 frames · 630.48 seconds
Convert
- Timecode
- 01:00:00:00
- Frames
- 90,000
- Seconds
- 3,600
How it works
- Choose the frame rate of your project. For 29.97 fps, tick drop-frame if your timecode uses semicolons.
- Enter two timecodes as HH:MM:SS:FF and press add or subtract to get the result with its frame count.
- To convert, pick what you have — a timecode, a frame count or seconds — and read the other two values.
- Copy the result back into your editing software.
What people use it for
Edit lists and durations
Work out the length of a clip from its in and out points, or the start of the next clip in a sequence.
Subtitles and captions
Convert a frame-based timecode from an editor into the seconds a subtitle file needs.
Broadcast delivery
Check a programme duration or a part start time against the 29.97 drop-frame timecode of a deliverable.
Questions
- How is a timecode turned into frames?
- Frames = ((hours × 3600) + (minutes × 60) + seconds) × frame rate + frames. At 25 fps, 00:00:10:12 is 10 × 25 + 12 = 262 frames. Adding or subtracting timecodes is done on these frame counts, then converted back.
- What is drop-frame timecode?
- NTSC video runs at 30000/1001 (about 29.97) frames per second, but a plain 30-frame counter would drift from the clock by 3.6 seconds an hour. Drop-frame skips the labels 00 and 01 at the start of every minute except each tenth minute — no picture is dropped, only numbers — so the timecode matches real time. It is written with a semicolon before the frames, like 00:01:00;02.
- How are seconds calculated?
- Seconds = frames ÷ the real frame rate, which is 24, 25 or 30, or 30000/1001 for 29.97. Seconds to frames is the reverse, rounded to the nearest frame.