Fix subtitles that are out of sync

The words arrive a second before the mouth moves, or a beat too late, and it ruins the film. This is a two-second fix, and it only needs doing once per file.

Why subtitles drift

A subtitle file is timed against one particular release of a film. Use it with a different cut, a version with the studio logos trimmed, or a different frame rate, and every line lands at the wrong moment — usually by a consistent offset rather than randomly.

Shifting them into place

Open the subtitle delay control and nudge the timing while the film keeps playing. Watch one line of dialogue and adjust until the words land with the lips. Because the offset is constant, fixing one line fixes the whole film.

It is remembered

The offset is saved against that file. Close the film, come back next week, and the subtitles are still correct — you never do it twice.

Constant offset or growing drift?

The two look similar for the first minute and need different answers. A constant offset — every line early or late by the same amount — is the common case, and one adjustment fixes the whole film. Drift that widens as the film runs means the subtitle was made for a version at a different frame rate; no single offset will hold, and another subtitle file for your release is the quicker route.

A quick way to find the right offset

Rather than guessing, find a moment where someone starts speaking clearly, and watch one line. If the words appear before the mouth moves, the subtitle is early and needs delaying. Adjust in small steps — a quarter of a second is usually enough, and anything over a second or two suggests the wrong file rather than a timing problem.

When it is the audio that has drifted

If the subtitles match the words but the sound itself lags the lips, the subtitle is not the problem. Audio delay is a separate control for exactly this. Bluetooth headphones are a common cause, adding a delay of their own that has nothing to do with the file — testing with wired output rules that out in seconds.