Reverse Audio plays a whole piece of sound backwards, from the end to the beginning. Pure audio uses ffmpeg's areverse and keeps its original format where possible; video has two routes — “Reverse picture and sound together” reverses the picture, applies areverse to the sound and re-encodes to MP4, while “Reverse the sound only” discards the picture and outputs MP3 only.

The reverse filters have to buffer the whole set of samples or video frames before emitting them in the opposite order, so memory pressure is higher than for ordinary sequential transcoding. The code sets a hard limit on reversing picture and sound together: when a duration above 60 seconds is detected the button is disabled and the page suggests trimming a shorter clip first.

1. 01Choose a fileaudio or video both work; switch to the “Reverse” tab.
2. 02For video, choose a modepick “Reverse picture and sound together” for a fully reversed video, or “Reverse the sound only” to extract a reversed audio effect. Pure audio goes straight to reversing.
3. 03Check the limitsreversing picture and sound together is refused beyond 60 seconds, and a video with no audio track cannot use the sound-only mode.
4. 04Start reversingafter confirming the ffmpeg command click “Start reversing” and download the audio, MP3 or MP4 result.

Memory behaviour

reverse and areverse buffer the entire content, so large files and long audio are more likely than sequential filters to exhaust browser memory.

Video length

reversing picture and sound together is limited to 60 seconds; beyond that, trim a clip in “Cut” first.

Video output

a full reversal is always re-encoded to MP4 and does not keep the original container; the sound-only mode always outputs MP3.

Videos with no audio track

only the picture can be reversed, and “Reverse the sound only” is not available.

What it does not do

it cannot reverse just one section, and there is no loop playback or keyframe editing; use “Video Cut” or “Audio Cut and Merge” to take a range first.

The media file is reversed only inside the browser by ffmpeg.wasm and is never uploaded; the first use of the workbench downloads about 31–32 MB of single-threaded ffmpeg core from the site's asset domain or jsDelivr.