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THE BROWSER MEDIA WORKBENCH

FFmpeg OnlineYour media. Your command.

Remux videos, merge audio, extract sound and run FFmpeg commands — right in your browser.

Files stay on your deviceFree · No sign-up

Workspace 00

250 MB total workspace limit. Smaller files work best on mobile.

Add video, audio, images or a playlist to get started.

Command

Files stay on your device

One FFmpeg command at a time. Use /inputs/filename for inputs and a plain filename for outputs. Shell pipes and scripts are not supported.

Ready when you are. Choose files and a command to begin.

Console

Ready when you are. Choose files and a command to begin.

Feature guide

Add your files, choose a quick command and its inputs, then click “Use template”. Review the command, run it and download the output from the workspace.

Remux to MP4

Put existing media streams into an MP4 container while keeping their original video and audio quality.

How to use

Add a video, choose the first input and use the template. Run it to create output.mp4.

Keep in mind

The template copies all streams with -c copy. It does not compress or repair damaged media. Every copied stream must be compatible with MP4; otherwise adjust the command or transcode.

Merge video + audio

Combine the picture from one file with sound from another, for adding narration or replacing a soundtrack.

How to use

Add both files, select the video as the first input and audio as the second, then use the template and run it to create merged.mp4.

Keep in mind

Uses only the first video track from input one and the first audio track from input two. Original video audio is omitted. Streams are copied and must fit MP4; output ends with the shorter input.

Extract MP3 audio

Convert sound from a video or audio file to MP3 for listening, editing or saving separately.

How to use

Choose a file containing audio, use the template and run it to create audio.mp3.

Keep in mind

This re-encodes audio with a lossy MP3 encoder; it is not lossless extraction of the original track. FFmpeg selects one audio track automatically. Files without audio cannot use this template.

Remove audio

Remove sound from a video for silent playback or a new voice-over.

How to use

Choose a video, use the template and run it to create silent.mp4.

Keep in mind

Keeps only the first video track, without audio, subtitles or other tracks. The picture is copied without re-encoding, but its codec must still be compatible with MP4.

Convert to AAC

Encode sound from a video or audio file as AAC in an M4A container.

How to use

Choose a file containing audio, use the template and run it to create audio.m4a.

Keep in mind

The default bitrate is 192 kb/s; edit -b:a 192k to change it. This is lossy re-encoding. The result is an .m4a file, not a raw AAC file.

Join TS videos

Join compatible TS video segments in sequence into one file.

How to use

Keep only the TS segments to join in the workspace and check their displayed order. Use the template and run it to create joined.ts. To reorder, save and remove files, then add them individually in the desired sequence.

Keep in mind

Uses every workspace file, including earlier outputs. The first-input selector does not change the order. Segments need matching codecs and stream parameters; different resolutions or audio layouts cannot be mixed arbitrarily.

Trim first 10 seconds

Save a short video excerpt, starting with the first 10 seconds by default.

How to use

Choose a video and use the template. Edit -ss 00:00:00 for the start and -t 10 for the duration in seconds. Run it to create clip.mp4.

Keep in mind

Stream copy can align the start to a keyframe, so cuts are not frame-accurate. No extra footage is added beyond the source duration. Frame-accurate trimming requires a custom re-encoding command.

Create a 5-second GIF

Turn a short video excerpt into a silent animated GIF for demonstrations or sharing.

How to use

Choose a video and use the template to create preview.gif from the first 5 seconds at 10 fps and 480 pixels wide. Edit -t, fps and scale to adjust it.

Keep in mind

GIF has no sound. Encoding can take time and produce large files, and colors may differ from the source. Start with a short excerpt.

FFmpeg help

Show basic command help for the bundled FFmpeg version in the console.

How to use

Choose “FFmpeg help”, use the template and run it. No input files are needed.

Keep in mind

Help appears in the console and does not create downloadable media. Available codecs and options may differ from a desktop FFmpeg installation.

Workspace and custom commands

Custom commands

Edit FFmpeg arguments to go beyond the templates or customize their behavior.

How to use

Use /inputs/filename for inputs and a plain filename for outputs, for example: ffmpeg -i "/inputs/video.mp4" -c copy result.mp4. Quote paths that contain spaces.

Keep in mind

Run one command at a time; shell pipes, scripts and command chains are unsupported. After changing input selectors, click “Use template” again to update the editor. The editor text is what runs.

Add files and reuse outputs

Add multiple local files and keep generated outputs in the workspace for further processing.

How to use

Choose files or drop them onto the add-files area. Duplicate names get a number. Outputs can be selected as inputs in the next operation.

Keep in mind

The 250 MB workspace limit includes inputs and outputs. Files are not uploaded. Refreshing or closing the page clears the workspace. Playlist segments must also be added with correctly matching paths.

Preview and download

Check supported media and save the files you want to keep.

How to use

Use “Preview” to view video, audio or images, and “Download” to save an individual file. Closing the preview does not remove the file.

Keep in mind

If the browser cannot play a format, download it for a compatible player. Outputs are not saved to your device automatically; download them before clearing or leaving the page.

Copy and insert filenames

Avoid typing mistakes when building a command.

How to use

“Copy name” copies the displayed filename. “Insert name” inserts a quoted /inputs/ path at the editor cursor, replacing selected text.

Keep in mind

Copied names do not include /inputs/; add that prefix when typing input paths. Check spaces between arguments after insertion. Options such as -i are not inserted automatically.

Console and stopping a command

Read engine messages and errors, or interrupt a long-running operation.

How to use

Run the command and use “Stop” to interrupt it. The console scrolls with new messages; “Clear log” removes the displayed messages.

Keep in mind

Stopping keeps existing workspace files but discards unfinished results. Each run resets the console, which shows roughly the latest 400 lines. Clearing logs does not stop processing.

Remove files and clear the workspace

Free workspace space by removing files you no longer need.

How to use

Use “Remove” for an individual file or “Clear workspace” for all inputs and outputs. Stop any running task first.

Keep in mind

Removal is immediate and cannot be undone in the page. It does not delete original files on your device. Removed outputs that were not downloaded must be generated again.

Before you run

01

The engine downloads on first use (about 30 MB). Processing uses your browser’s memory; closing this tab clears the workspace.

02

Copying streams is fast and keeps quality. Transcoding and GIF creation take longer. Container and codec compatibility still apply.

03

Trim uses stream copy, so cuts may align to keyframes. Join expects compatible TS streams. Download results before clearing the workspace.