Timecode and frames
Convert timecode to a frame number and back, compute the real duration and show how far an NDF timecode drifts.
Frame number
1500
00:01:00:00
Real duration
60 s
Timecode drift
The timecode matches real time
Reverse conversion
Seconds → timecode at the selected frame rate.
Timecode
00:01:00:00
Convert frames between frame rates
How many frames and what duration you get at another frame rate.
Keeping the duration
1 440 frames
This is the frame count at the target frame rate when the duration stays the same.
Keeping the frame count
62.5 s
This is the duration at the target frame rate when the frames stay the same.
How we calculate
Data tier:Aprimary sourceVerified: 03 Nov 2026Formula
frame number = hours × 3600 × nominal fps + minutes × 60 × nominal fps + seconds × nominal fps + frame within the second; timecode = frame number counted at the nominal rate of the counter; drift = (actual frames ÷ nominal fps) − real time
Data sources
- Frame numbering and the drop-frame rule: SMPTE 12M timecode standard — two frame numbers are dropped at the start of every minute except every tenth
- NDF drift is computed arithmetically: the nominal counter rate (30, 60, 24) against the actual signal rate (29.97, 59.94, 23.976) — verified 03.11.2026
The value is confirmed by a primary source — the vendor document.
Caveat
Drop-frame is exact for 29.97 and 59.94 fps. For 23.976 fps only NDF applies — the 3.6 s per hour drift is there too.