Timecode and Clip Duration, Explained

Timecode is the universal clock of film, television, and digital video production. Written as HH:MM:SS:FF, it breaks every frame of footage into hours, minutes, seconds, and a frame number, letting editors, colorists, sound designers, and DITs stay in sync across every tool in the pipeline. Knowing the exact duration between two timecodes is essential for editing workflows, broadcast delivery, and accurate project planning.

The Timecode Duration Calculator makes this instant: enter a start timecode, an end timecode, and a frame rate, and it returns the exact duration in timecode format, total frames, and seconds — live as you type.

Why Frame Rate Matters

The same one-minute span of clock time is a very different number of frames depending on your project’s frame rate: 1,440 frames at 24fps, 1,500 at 25fps, or 1,800 at 30fps. Selecting the correct frame rate before conforming an EDL, building a pull list, or calculating a delivery runtime avoids the kind of off-by-one-second errors that cause real problems downstream.

Drop-Frame vs. Non-Drop-Frame

NTSC frame rates like 29.97 and 59.94 don’t divide evenly into whole seconds, which is why broadcast timecode comes in two flavors. Non-drop-frame timecode counts every frame sequentially and drifts slowly out of sync with real clock time over a long program. Drop-frame timecode periodically skips frame numbers (not actual frames) to stay aligned with real time. This calculator treats 29.97 and 59.94 as non-drop for simplicity — always confirm which standard your project uses before conforming a broadcast delivery.

This tool is especially useful for:

• Editors and assistant editors who need exact clip runtimes for a pull list or EDL.
• DITs and post supervisors confirming frame-accurate durations across a project.
• Broadcast producers checking that segments match strict runtime requirements.