How to reverse a slow-motion action replay
- Step 1Isolate the play you want to replay — Trim the goal, dunk, or trick to a tight window with the lossless-trimmer. A short replay clip reverses fast and keeps the effect punchy.
- Step 2Decide the order: reverse then slow, or slow then reverse — If your source is normal speed, reverse here first, then slow it in the speed controller. If your source is already high-frame-rate slow-mo, reverse it directly — it is already slow. Both orders work; pick based on your footage.
- Step 3Reverse the clip in this tool — Drop the clip on the reverser. No options — JAD reverses video and audio together and returns an H.264 MP4. The ball rewinds to the boot, the jumper to the release.
- Step 4Add slow motion with the speed controller — Send the reversed MP4 to the video-speed-controller and set 0.5x (or lower) for the dramatic half-speed reverse. The speed controller can keep audio pitch natural if you keep sound.
- Step 5Mind the audio — Reversed crowd noise and commentary can sound strange. For a clean replay, strip the reversed audio (via audio-track-extractor) and lay broadcast-style music or commentary on top in your editor.
- Step 6Cut into the highlight reel — Drop the reversed (and optionally slowed) MP4 into your reel, often after the forward play, so the viewer sees it happen, then watches it rewind in slow motion.
Reverse vs slow-motion: two different tools
The reverser only reverses; speed changes live in the speed controller. Combine them for the broadcast reverse-replay.
| Effect | Tool | Notes |
|---|---|---|
| Play it backwards | video-reverser (this tool) | reverse + areverse; no speed change; output MP4 CRF 20 |
| Slow it down | video-speed-controller | Retimes the clip; can preserve audio pitch |
| Reverse + slow (the replay) | Both, in sequence | Reverse here, then slow — or reverse already-slow-mo source |
| Trim the replay window | lossless-trimmer | Instant, no re-encode; do before reversing for speed |
Reverser output and limits for sports footage
Fixed encode and the size/batch caps that matter for high-bitrate action-cam files.
| Item | Value |
|---|---|
| Output | H.264 MP4, CRF 20, AAC 192 kbps |
| Speed change | None — use the speed controller |
| Long-clip handling | Auto chunked above 60 s (8 s segments) |
| Free tier | 1 GB per file, 1 file |
| Pro tier | 10 GB per file, 5 files |
| Pro-media / Developer | 100 GB per file; 50 files / unlimited |
Cookbook
Reverse-replay recipes pairing the reverser with the speed controller and trimmer. The reverse step has no options.
Forward play, then slow reverse
The classic broadcast move: show it live, then rewind in slow motion.
1. Trim the goal -> goal.mp4 (3 s) (lossless-trimmer) 2. Reverse goal.mp4 -> goal_rev.mp4 (this tool) 3. Slow goal_rev.mp4 to 0.5x -> goal_rev_slow.mp4 (speed-controller) 4. In editor: place goal.mp4, then goal_rev_slow.mp4
Reverse an already-slow-mo source
If you filmed at 120/240 fps, the clip is already slow. Just reverse it.
Input: dunk_120fps.mp4 (slow-mo as shot) Reverse here -> dunk_120fps_rev.mp4 Result: slow-motion reverse without a separate speed step.
Half-speed reverse with clean audio
Reversed crowd noise sounds odd; strip it and add music.
1. Reverse play.mp4 -> play_rev.mp4 (reversed audio) 2. Remove audio (audio-track-extractor) -> play_rev_silent.mp4 3. Slow to 0.5x (speed-controller) -> play_rev_slow.mp4 4. Add broadcast music/commentary in editor.
Ball-to-boot rewind
Tight window so the rewind reads instantly.
1. Trim from contact back to the run-up -> strike.mp4 2. Reverse strike.mp4 -> strike_rev.mp4 Result: the ball flies back to the boot; pair with 0.5x for drama.
Long match clip routed through chunked reverse
Reversing a long capture triggers the memory-safe path; better to trim first.
Input: half1.mp4 (45 min) -- reversing this runs chunked & is huge
Better: trim to the 4 s goal -> goal.mp4
reverse goal.mp4 -> goal_rev.mp4 (single pass, fast)Edge cases and what actually happens
Expecting the reverser to slow the clip too
Not supportedThe reverser only reverses — it does not change speed or frame rate. For the slow-motion half of a reverse replay, run the reversed MP4 through the video-speed-controller. The two operations are separate by design.
Reversed audio (crowd/commentary) sounds wrong
Strip and replaceareverse reverses the soundtrack, so commentary and crowd noise play backward. For a polished replay, remove the reversed audio with the audio-track-extractor and add forward music or fresh commentary in your editor.
High-frame-rate slow-mo source is large
Mind the tier cap120/240 fps action-cam files are big. Free caps at 1 GB, Pro at 10 GB, Pro-media and Developer at 100 GB. A file over the cap is rejected before processing — trim to the replay window first to stay under the limit and on the fast reverse path.
Reverse order question: reverse then slow, or slow then reverse
Either worksReversing and slowing commute visually for a constant-frame-rate clip — the reversed-then-slowed result matches slowed-then-reversed. Pick the order that fits your footage: reverse a normal clip here then slow it, or reverse an already-slow-mo source directly.
Frame rate looks choppy after reversing
Source frame rateThe reverser preserves frame count; it adds no frames. If a slowed reverse looks choppy, the source frame rate is too low for the slowdown — there are not enough real frames. Shoot at a higher fps for slow-mo, or accept the source's smoothness limit.
Long match capture reversed whole
By designOver 60 s the reverse auto-routes to the chunked pipeline. Correct, but you do not want to reverse a whole half. Trim to the play first; the short clip reverses in the fast single pass.
Output is MP4, source was MOV/MKV from the action cam
ExpectedReversal re-encodes, so the output is always H.264 MP4 — ideal for cutting into a reel. The original container is decoded and re-encoded; quality stays high at CRF 20.
Variable frame rate from a phone slow-mo mode
Reverses correctlyPhone slow-mo modes often write VFR. The reverse is correct, but combining with the speed controller is cleaner if you convert to a constant frame rate first so the retiming math is exact.
Frequently asked questions
Does the reverser also slow the clip for the replay?
No — it only reverses. The slow-motion half comes from the video-speed-controller. For a broadcast reverse replay, reverse the clip here, then set 0.5x (or lower) in the speed controller.
Should I reverse first or slow first?
Either works for a constant-frame-rate clip — the result is the same. If your source is normal speed, reverse here then slow. If you already shot high-frame-rate slow-mo, just reverse it; it is already slow.
The reversed commentary sounds weird — can I remove it?
Yes. The reverser always reverses audio (areverse), so commentary plays backward. Reverse here, strip the reversed audio with the audio-track-extractor, and lay forward music or fresh commentary over the replay in your editor.
Will my action-cam footage be uploaded?
No. The reverser runs FFmpeg.wasm locally in your browser tab. Your footage and the reversed result stay on your device.
What output format do I get for my reel?
An H.264 MP4 at CRF 20 with AAC audio — it cuts straight into any editor and uploads to any platform without further conversion.
Can I reverse a 240 fps slow-mo clip?
Yes — the reverser preserves the frame count and reverses the order. A high-frame-rate clip stays high-frame-rate, so the reverse is already slow-motion smooth without a separate speed step.
Why does my slowed reverse look choppy?
The reverser does not add frames. If a slowed reverse looks choppy, the source frame rate is too low for the slowdown factor. For dramatic slow reverses, film at a higher fps so there are enough real frames.
How long a clip can I reverse?
No duration cap — limits are by file size (1 GB Free, 10 GB Pro, 100 GB Pro-media/Developer). Over 60 seconds the reverse runs via an automatic chunked pipeline. For replays you want a short clip anyway, so trim first.
Can I batch a few replay clips at once?
Batch count depends on tier: 1 on Free, up to 5 on Pro, up to 50 on Pro-media, unlimited on Developer. Each clip reverses into its own MP4.
Does reversing degrade the highlight quality?
One generation of re-encoding happens because reversal can't stream-copy. At CRF 20 the loss is minimal. Reverse and slow last in your chain to avoid stacking re-encodes.
Can I make the reverse loop back and forth?
Yes — join the forward and reversed copies in the video merger for a ping-pong of the play, like a boomerang. See the boomerang recipe.
Is there a watermark on the output?
No. JAD never watermarks output, so the reversed replay drops cleanly into your reel.
Privacy first
Every JAD Video tool runs entirely in your browser via WebCodecs and FFmpeg (WebAssembly). Your video files never leave your device — verified by zero outbound network requests during processing.