Cut Video
Trim the start and end of a video and keep only the part you need. Files never leave your device.
No upload · Processed in your browserMP4 · MOV · WebM · MKV · 3GP · AVI · WMV · FLV1 GB per file (recommended)As of 2026.10.01
No re-encoding, so it is quick and keeps the original quality. The start may move back slightly to the previous keyframe
How to use Cut Video
- 1Drag and drop one video or pick it with [Choose files]. The video and a range strip appear in the edit preview
- 2Drag the handles or type seconds into the Start and End fields to set the part to keep, choose a Cutting method (Fast or Accurate), then press [Start]
- 3Check the actual length and message on the result card, then save with [Download]
The big number on the result card is the size of the result file, with the resolution, actual length and codecs below it. Each result keeps the original name with -cut added, as in clip.mp4 → clip-cut.mp4. Fast keeps the original format (3GP becomes MP4), and Accurate saves MP4.
You can add one video at a time. We recommend up to 1 GB on desktop and 100 MB on mobile. Going over the recommendation shows a warning, but you can still continue. Files over 4 GB are not processed. For AVI, WMV and FLV, which go through the fallback engine, we recommend up to 300 MB on desktop and 100 MB on mobile, and files over 700 MB are not processed.
- Example 1 · 10–20 s of a 1080p video, Fast
1080p-30s.mp4 (1920×1080, 30 s, H.264 + AAC) · 5.8 MB · 10–20 s · Fast (default)
Measured in Chrome on desktop · synthetic test video (test pattern + 440 Hz tone, a keyframe every 2 seconds) · 10 s is a keyframe, so the cut starts exactly where chosen
→ 1080p-30s-cut.mp4 · 1.9 MB · 10.0 s · neither video nor audio re-encoded
- Example 2 · Fast, starting between keyframes
Same 1080p-30s.mp4 · 11–20 s · Fast
Measured in Chrome on desktop · synthetic test video (a keyframe every 2 seconds)
→ Cut from the previous keyframe at 10.0 s · 10.0 s long · message “Cut from 10.0s to match a keyframe”
- Example 3 · The same range, Accurate
1080p-30s.mp4 · 5.8 MB · 10–20 s · Accurate
Measured in Chrome on desktop · synthetic test video
→ 1080p-30s-cut.mp4 · 2.3 MB · 10.0 s · re-encoded to H.264 + AAC at 1920×1080
- Example 4 · A WebM with a keyframe only at 0 s
vp9-opus.webm (640×360, 10 s, VP9 + Opus) · 829 KB · 2–6 s · Fast
Measured in Chrome on desktop · synthetic test video · to start exactly at 2 s, choose Accurate (the result is then MP4)
→ vp9-opus-cut.webm · 499 KB · 5.98 s · cut from 0 s, because its only keyframe is at 0 s
Example figures vary by file and device.
Cut Video options explained
- Range to keep
- Sets the start and end of the part you keep. At first the whole video is selected. Drag the handles on the range strip, or type seconds into the Start and End fields (90 for 1 minute 30 seconds). Values go in 0.1-second steps: select a handle and press the arrow keys to move it 0.1 s, or 1 s with Shift. [Set start to current position] and [Set end to current position] use the preview video's current playback position. The range must be at least 0.5 s long. For AVI, WMV and FLV the length can't be read when you add the file, so there's no range strip and you type the numbers into the Start and End fields.
- Cutting method
- “Fast” (default) cuts without re-encoding, so the quality is unchanged and the result keeps the original format (3GP becomes MP4). Without re-encoding, though, the video can only start at a keyframe. If the start you chose isn't a keyframe, it moves back to the previous one and the result says “Cut from n s to match a keyframe”. “Accurate” cuts exactly where you chose and re-encodes to MP4 (H.264 + AAC at 128kbps). Resolution and frame rate stay the same (width and height rounded to even numbers). The video bitrate is width × height × fps × 0.10, and if that's higher than the original's, 80% of the original bitrate is used instead. It takes longer and goes through lossy compression one more time. Choose Fast if a start a few seconds early is fine, and Accurate when the start has to be exact.
- Metadata and tracks
- This isn't a setting you can turn on or off; it always works the same way. Metadata such as shooting location and device info is not carried over to the result. One main video track and one main audio track are kept. When Accurate re-encodes the video, the rotation info of videos shot in portrait is applied to the pixels.
Cut Video: frequently asked questions
Are my videos sent to a server?
No. Cutting happens inside this browser and your files are never sent off your device. To check it yourself, follow the steps on the How it works page.
What's the difference between Fast and Accurate?
Fast moves the compressed video and audio data you need into a new file without re-encoding. Quality and format stay the same, but the start snaps to a keyframe. Accurate cuts at the exact point and re-encodes to an H.264 + AAC MP4. Cutting 10–20 s from the test file 1080p-30s.mp4 (5.8 MB) gave 1.9 MB with Fast and 2.3 MB with Accurate, both 10.0 s long. In this file 10 s is a keyframe, so Fast cut at the same point.
The cut starts earlier than I chose.
With Fast, if the start you chose isn't a keyframe, the cut begins at the previous keyframe. A keyframe is a complete frame that can be decoded without the frames before it, and without re-encoding a video can only start at one. Cutting 11–20 s from a test file with a keyframe every 2 seconds started at 10.0 s and showed “Cut from 10.0s to match a keyframe”. A test WebM whose only keyframe is at 0 s was cut from 0 s when 2–6 s was chosen, giving 5.98 s. To cut at the exact point, choose Accurate.
Can I cut AVI, WMV or FLV videos?
Yes. These formats, and codecs this browser can't handle, go through the fallback engine (FFmpeg). While it downloads the first time, you'll see “Preparing the processing engine · about 31 MB, first time only”. For AVI, WMV and FLV the length can't be read when you add the file, so there's no range strip; type the seconds into the Start and End fields. Fast keeps the original format and Accurate saves MP4. We recommend up to 300 MB on desktop and 100 MB on mobile, and files over 700 MB are not processed.
Can I cut a long video on my phone?
On mobile we recommend up to 100 MB. Larger files show the warning “This device may stall while processing (up to 100 MB recommended)”, but you can still continue. Fast doesn't re-encode, so it finishes sooner than Accurate. Keep this page open while processing.
Can I cut several parts at once?
Each run keeps one range. If you need another part, use the original video again with a different range. Your original file isn't changed.
Related tools
How it works · Engine · Notes
- Processed in: this browser (your device)
- Engine: Mediabunny (MPL-2.0) · WebCodecs (built into the browser) (—) · Mediabunny AAC encoder (LGPL-2.1-or-later) · FFmpeg (ffmpeg.wasm, fallback) (GPL-2.0-or-later)
- Cutting runs inside this browser with Mediabunny, and files are not sent to a server. Fast only moves the data without re-encoding, and Accurate re-encodes with the browser's built-in video engine (WebCodecs).
- AVI, WMV and FLV files, and codecs this browser can't handle, are processed with a fallback engine (FFmpeg, WebAssembly, about 31 MB) that is downloaded the first time and kept in the browser cache. The cutting method and result format are the same whichever engine is used.
- With Fast, the start may move back to the previous keyframe; the result card shows the actual length of what was cut.
- Metadata such as shooting location and device info is not carried over.
- As of 2026.10.01
- Changelog: 2026.10.01 First release