How do I reverse a video without uploading it?

Open it here. Your browser reads the file and decodes the selected part; this page writes available decoded pictures last first through your browser's own WebCodecs encoder, then offers the file as a download. Nothing is sent to a server, and there is no account.

Can I reverse just part of a video?

Yes. Type a start and an end in seconds (or as minutes and seconds, like 1:05.5), or play the original and press Start here and End here. The selection moves out to whole source-frame intervals: 2.000 s to 7.500 s of a 30 fps clip selects frames 61 to 225, 165 frame intervals lasting 5.500 s. Whole clip sets the selection back to the entire video. Decoder omissions can affect the pictures and final length as described in the timing answer.

Does the sound play backwards too?

With Reversed, the sound is the source's own samples in reverse order: 5.500 s of 48 kHz stereo is 264,000 samples a channel, played last to first. An MP4 gets AAC at 128 kbps, at 44.1 or 48 kHz as the source had it or 48 kHz otherwise, and a WebM gets Opus at 128 kbps and 48 kHz; more than two channels are mixed down to stereo. Muted leaves the sound track out of the file entirely. If your browser cannot decode the sound, or it has more than 8 channels, Reversed is refused with the reason and Muted still works.

Will the reversed video have the same length and frame rate?

When every picture decodes, the source frame durations are kept in reverse order: three frames of 0.500 s become 3, 2, 1, each still 0.500 s, and variable frame durations keep their original rhythm. If the decoder omits a picture, the next available picture in reverse output covers that time where possible; uncovered time at the end can shorten the file. The readout reports omitted pictures. The finished length is measured against the chosen interval to one average source frame (the interval length divided by its frame count), and the result says whether it landed within that or how far it missed.

Why does my phone video come out the right way up?

Phones often store video sideways with a rotation flag that players follow. This page applies the flag to the picture, so the reversed file is written upright at the size the original plays at and carries no flag. H.264 and the other encoders need even sides, so a side of odd length loses one pixel.

Which formats can it open and save, and how big can the video be?

It reads MP4, MOV, WebM, MKV and MPEG-TS, as long as your browser can decode the video inside, and refuses AVI, MPG, WMV and FLV by name. It writes H.264 or HEVC in an MP4, or VP9, VP8 or AV1 in a WebM, and asks your browser whether it can encode that codec at the video's size before any work starts. Videos up to 100 MB and two minutes are reversed, with frames up to 4096 px a side and 9,437,184 pixels, so 3840 x 2160 fits.

Does reversing a video lower its quality?

The picture has to be re-encoded, because the frames are written again in a new order, so some quality can be lost. It is encoded at a high quality setting, and reversed sound is encoded at 128 kbps.

Why does reversing take a while, and can I stop it?

Video decodes forwards only, so the page decodes a window of frames from the end of the part back, at most 60 frames or 256 MB of pictures at a time, writes them last first and releases them before decoding the window before it. A window starts on a key frame where one is in reach; when key frames are far apart, some frames are decoded more than once. Cancel stops the decoders and encoders, and nothing is written.

Is the video reverser free and without a watermark?

Reversing and saving the result are free and need no account. This page adds no watermark, logo or end card. A watermark already in the original picture stays in the reversed video.

Can I reverse a YouTube video by pasting its link?

No. This tool opens local video files, not YouTube links or streaming pages. It does not fetch or download videos from YouTube.

Can I use it on a phone, Mac or Windows computer?

It runs in the browser on your device, with no installation. Reversal needs WebCodecs video decoding and encoding, and support varies by browser, device and codec. The page checks the required codecs and explains a refusal; it has no server fallback.

Video Reverser

Open a video, choose the part to play backwards and save an MP4 or WebM, made locally with your browser's codecs. Reverse its sound or leave the sound track out with Muted. Decoded pictures are written last first using source frame timing; the result reports any pictures that could not be decoded.

Open a video to reverse

· or drop one anywhere on the stage

Never uploadedNo accountUp to 100 MBUp to 2 minutes

Interval: tos

Frames: none yet

Audio

Format

Output: none yet

Ready. Choose a video, or drop one on the stage.

A fixture displaying 1,2,3 in equal intervalsthree frames, 0.500 s each
exports 3,2,1, each still 0.500 s: 1.500 s in total
Audio reversed, then mutedstereo, 5.500 s at 48 kHz
reversed: 264,000 samples a channel in reverse order; muted: no sound track at all
Variable-frame-rate input300 frames, 10.000 s, frame lengths vary
each of 300 frames keeps its own length (30.0 to 40.0 ms) in reverse: 10.000 s in total, checked to one frame on the finished file

Choose the part to reverse by typing a start and an end, or by playing the original and pressing Start here and End here; Play original plays that part forwards. The times move out to whole frames: the start back to the start of the frame showing then, the end on to the end of the frame showing just before it. Reverse writes decoded pictures last first using the source frame timing. If a picture cannot be decoded, a neighbor can cover its time; uncovered time at the end can shorten the result. The readout reports omitted pictures and the measured length. The picture is written upright at the size it plays at, with any rotation flag applied, and a side of odd length loses one pixel because the encoders need even sides. Reversed sound is the source's samples in reverse order, encoded at 128 kbps: an MP4 gets AAC at 44.1 or 48 kHz as the source had it, or 48 kHz otherwise, a WebM gets Opus at 48 kHz, and more than two channels are mixed down to stereo. Muted leaves the sound track out of the file entirely rather than writing a silent one. Frames are decoded a window at a time from the end of the part back, at most 60 frames or 256 MB of pictures a window, and each window is released before the next is decoded. Only codecs this browser can decode and encode are used: every format is listed, and one this browser cannot write is refused with the reason as soon as it is chosen, before any work starts. When the work ends, the file is read back: its container, codecs, picture size and sound track must match the plan or it is not offered, and its length and where its sound starts are measured, not predicted.

Accuracy. Decoded pictures come out in reverse order using source frame timing; omitted pictures can make a neighbor last longer or shorten the result, and the finished length is measured against the chosen part to one average source frame. Reversed sound is the source's samples in reverse order, resampled or mixed down to stereo only where the output format needs it, and Muted leaves the sound track out entirely. Only codecs your browser can decode and encode are used, anything else is refused with the reason before work starts and never sent to a server, and files up to 100 MB and two minutes are re-encoded on your device a short window at a time, which can cost some quality.

The encoding is done by your browser, and the file handling by one open source library served from this site. Containers are read and written by Mediabunny 1.55.7 under the MPL-2.0 (licence text, the exact package, source), bundled unmodified. Video and sound are decoded and encoded by the WebCodecs codecs built into your browser, which is why the formats on offer depend on it.

Common questions

How do I reverse a video without uploading it?: Open it here. Your browser reads the file and decodes the selected part; this page writes available decoded pictures last first through your browser's own WebCodecs encoder, then offers the file as a download. Nothing is sent to a server, and there is no account.
Can I reverse just part of a video?: Yes. Type a start and an end in seconds (or as minutes and seconds, like 1:05.5), or play the original and press Start here and End here. The selection moves out to whole source-frame intervals: 2.000 s to 7.500 s of a 30 fps clip selects frames 61 to 225, 165 frame intervals lasting 5.500 s. Whole clip sets the selection back to the entire video. Decoder omissions can affect the pictures and final length as described in the timing answer.
Does the sound play backwards too?: With Reversed, the sound is the source's own samples in reverse order: 5.500 s of 48 kHz stereo is 264,000 samples a channel, played last to first. An MP4 gets AAC at 128 kbps, at 44.1 or 48 kHz as the source had it or 48 kHz otherwise, and a WebM gets Opus at 128 kbps and 48 kHz; more than two channels are mixed down to stereo. Muted leaves the sound track out of the file entirely. If your browser cannot decode the sound, or it has more than 8 channels, Reversed is refused with the reason and Muted still works.
Will the reversed video have the same length and frame rate?: When every picture decodes, the source frame durations are kept in reverse order: three frames of 0.500 s become 3, 2, 1, each still 0.500 s, and variable frame durations keep their original rhythm. If the decoder omits a picture, the next available picture in reverse output covers that time where possible; uncovered time at the end can shorten the file. The readout reports omitted pictures. The finished length is measured against the chosen interval to one average source frame (the interval length divided by its frame count), and the result says whether it landed within that or how far it missed.
Why does my phone video come out the right way up?: Phones often store video sideways with a rotation flag that players follow. This page applies the flag to the picture, so the reversed file is written upright at the size the original plays at and carries no flag. H.264 and the other encoders need even sides, so a side of odd length loses one pixel.
Which formats can it open and save, and how big can the video be?: It reads MP4, MOV, WebM, MKV and MPEG-TS, as long as your browser can decode the video inside, and refuses AVI, MPG, WMV and FLV by name. It writes H.264 or HEVC in an MP4, or VP9, VP8 or AV1 in a WebM, and asks your browser whether it can encode that codec at the video's size before any work starts. Videos up to 100 MB and two minutes are reversed, with frames up to 4096 px a side and 9,437,184 pixels, so 3840 x 2160 fits.
Does reversing a video lower its quality?: The picture has to be re-encoded, because the frames are written again in a new order, so some quality can be lost. It is encoded at a high quality setting, and reversed sound is encoded at 128 kbps.
Why does reversing take a while, and can I stop it?: Video decodes forwards only, so the page decodes a window of frames from the end of the part back, at most 60 frames or 256 MB of pictures at a time, writes them last first and releases them before decoding the window before it. A window starts on a key frame where one is in reach; when key frames are far apart, some frames are decoded more than once. Cancel stops the decoders and encoders, and nothing is written.
Is the video reverser free and without a watermark?: Reversing and saving the result are free and need no account. This page adds no watermark, logo or end card. A watermark already in the original picture stays in the reversed video.
Can I reverse a YouTube video by pasting its link?: No. This tool opens local video files, not YouTube links or streaming pages. It does not fetch or download videos from YouTube.
Can I use it on a phone, Mac or Windows computer?: It runs in the browser on your device, with no installation. Reversal needs WebCodecs video decoding and encoding, and support varies by browser, device and codec. The page checks the required codecs and explains a refusal; it has no server fallback.

Decoded pictures come out in reverse order using source frame timing; omitted pictures can make a neighbor last longer or shorten the result, and the finished length is measured against the chosen part to one average source frame. Reversed sound is the source's samples in reverse order, resampled or mixed down to stereo only where the output format needs it, and Muted leaves the sound track out entirely. Only codecs your browser can decode and encode are used, anything else is refused with the reason before work starts and never sent to a server, and files up to 100 MB and two minutes are re-encoded on your device a short window at a time, which can cost some quality.