Trim a video without uploading it
The TubePull Video Trimmer cuts a video file down to the part you want, inside your browser. Choose a file, set a start and an end time, and download the clip. The video is read from your disk and processed on your own device, so it is never uploaded to TubePull or to any other server. The trimmer is free, needs no account and adds no watermark.
You can cut in two ways. A fast cut copies the original video and audio without re-encoding them. A precise cut re-encodes the video so the clip starts on the exact frame you chose. The result can stay in the original format or be saved as MP4 or WebM.
Fast cut or precise cut?
| Fast cut (no re-encoding) | Precise cut (re-encodes the video) | |
|---|---|---|
| Quality | Same as the original: every video and audio packet is copied unchanged | The video is encoded again, which can lower the quality slightly |
| Start of the clip | The keyframe at or before your start time | The frame shown at your start time |
| End of the clip | Your end time, sometimes plus a frame or two | The last frame before your end time |
| Speed | Usually quicker, because nothing is decoded or encoded | Depends on the clip length and your device |
| Good for | Long recordings, quick shares, keeping the original quality | Clips that must start on a given frame, changing the format |
Why a fast cut can start a little early
Compressed video stores a complete picture only at keyframes, which are often a few seconds apart. The frames in between record only what changed, so a copied clip has to begin at a keyframe. The trimmer starts a fast cut at the last keyframe at or before your start time, and shows that keyframe's time while you choose, so you know where the clip will begin. If the clip does start earlier than you asked, the result lists the requested start, the actual start and the difference in seconds. A fast cut can also run a frame or two past your end time, because the frames that the last moments depend on are kept.
Fast cut is turned off, and Precise cut is used, when there is no keyframe at or before your start time, or when the output format can't hold the original codecs. H.264 video can't go into WebM, for example.
Output formats
- Keep original writes the same container and file extension as your file, such as MP4, MOV, MKV or AVI. With Precise cut, the video is re-encoded in the original codec when your browser can encode it, and in H.264 otherwise (VP9 or VP8 for a WebM file). If your browser can't write the original container, this option is turned off and MP4 is selected.
- MP4 with Precise cut gives H.264 video and AAC audio, which plays on almost every phone, computer and TV.
- WebM with Precise cut gives VP9 video and Opus audio, or VP8 and Opus when the compatibility engine does the work.
With Fast cut, MP4 and WebM copy the original tracks into the new container without re-encoding. The download is named after your file with "-trimmed" added, for example holiday-trimmed.mp4. To change a whole MKV, MOV, AVI or WebM file to MP4 without cutting it, use Convert to MP4. For a silent, looping animation of up to 30 seconds instead of a clip, Video to GIF makes a GIF from the part you mark. To chop a whole recording into a run of pieces of one length rather than keep a single clip, use the Video Splitter.
Which videos you can trim
The trimmer opens MP4, MOV, MKV, WebM, AVI, FLV, WMV, MPEG-TS and 3GP files, including recordings from iPhone and Android phones. It identifies the format from the file's content, so a file with the wrong extension still opens correctly. If your browser can't play the file, which is common with AVI and WMV, the trimmer shows a strip of thumbnails and the start and end frames instead of a preview, so you can still find your cut points.
Every audio track in the file is kept, in its original order. That matters for recordings with several languages or a separate commentary track. Subtitle tracks are not copied into the trimmed file. Files protected with DRM can't be processed.
What happens to your file
The trimmer reads your file inside the browser tab and processes it there. No part of the video, its file name or its details is sent in any network request. The only things the page downloads are the tool's own program files from TubePull.
Most jobs run on WebCodecs, the video encoders and decoders built into your browser, which can use your device's hardware. When a file or format is outside what your browser supports, the trimmer switches by itself to a compatibility engine: FFmpeg compiled to WebAssembly (ffmpeg.wasm). That engine is about 32 MB, downloads only when a job needs it, and then stays in your browser's cache. The licenses page lists the exact versions and links to their source code.
Limits and tips
- A clip must be at least 0.1 seconds long.
- Type times as seconds (75), minutes and seconds (1:15.5) or hours, minutes and seconds (0:01:15.250), with up to three decimal places.
- There is no fixed file size limit. Your device's memory and browser storage set the practical one. The compatibility engine won't start a job whose output would be larger than about 1.5 GB, and phones show a warning for files over 500 MB. If a job runs out of memory, choose a shorter range or use a desktop browser.
- For an exact start with Fast cut, move the start time onto the keyframe time the trimmer shows.
- Phone videos often have a variable frame rate. Both cut modes keep each frame's original timing, so sound and picture stay in step.
Is the video still online?
The trimmer works on files you already have. If the video is on YouTube, TikTok, Instagram or another site, save it with the TubePull downloader first. For a long video, Clip Range downloads just the part you need straight from the link. You can then open the file here for a frame-accurate cut, or try the other free video tools.