Add and subtract

Result
01:00:42;12
Frames
109,164
Real time
1 h 0 min 42.439 s

Convert

Timecode to frames and real time

Frames
107,892
Real time
59 min 59.996 s
At 25 fps
01:00:00:00 (same real time)

Frames to timecode

Timecode
00:00:48;00
Real time
48.048 s