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Photography & Media

Integer-Rate Non-Drop Timecode Calculator

What frame index corresponds to non-drop timecode, and what index follows a signed frame offset?

Measured values and planning assumptions
Supported: 0 to 23; whole numbers.
Supported: 0 to 59; whole numbers.
Supported: 0 to 59; whole numbers.
Supported: 0 to 239; whole numbers.
Supported: 1 to 240; whole numbers.
Supported: -1000000000 to 1000000000; whole numbers.

Method, formula and assumptions

Frame index = ((hours x 60 + minutes) x 60 + seconds) x integer FPS + frame field. Add signed frame offset; divide by exact FPS for elapsed seconds. No 24-hour wrap is applied.

Input definitions and supported units

  • Timecode hours: Whole-number count, from 0 to 23; zero is supported where the stated method permits it.
  • Timecode minutes: Whole-number count, from 0 to 59; zero is supported where the stated method permits it.
  • Timecode seconds: Whole-number count, from 0 to 59; zero is supported where the stated method permits it.
  • Timecode frame within second: Whole-number count, from 0 to 239; zero is supported where the stated method permits it.
  • Exact integer frames per second: Whole-number count, from 1 to 240; must be positive.
  • Signed frame offset: Whole-number count, from -1000000000 to 1000000000; signed values are supported.

Worked example with answer

01:02:03:12 at exact 24 fps is frame 89,364, or 3,723.5 seconds. Adding 48 frames gives index 89,412 and 3,725.5 seconds.

How to use the results

The first frame is index zero. Use this only for exact integer-rate non-drop timelines; fractional-rate timecode requires a different convention.

Results retain full precision internally and display up to four decimal places. Very small nonzero results use scientific notation rather than appearing as zero. Check the labels before comparing values across units.

Limitations and references

Explicitly excludes 23.976, 29.97, 59.94 and drop-frame labeling. It does not handle day rollover, discontinuous timecode or variable-frame-rate recordings.

The method is a self-contained arithmetic, geometric or explicitly stated mathematical model. There are no imported tariffs, empirical presets or equipment specifications; measured values and allowances must come from your own process.

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