Trim a video without losing quality

Pick a start and an end, and get just that part of the video as an MP4. The video is cut without re-encoding, so the quality stays exactly the same and it takes seconds, even for long recordings. It runs in your browser, so your video is never uploaded.

Drop a video hereChoose a video

MP4, MOV, MKV, AVI, or a Dahua or Hikvision recording. It stays on your device.

Choose a video

Your files stay on this device. Nothing is uploaded.

How to trim a video without losing quality

Add your video
Drop one video on the blue screen on this page or choose it from your device. Dahua .dav files and Hikvision exports are converted to MP4 first, which takes a few seconds.
Pick the start and end
Play the video and press Set start and Set end at the right moments, or type the times, like 1:05 or 65.5. For CCTV footage, each time is also shown on the recorder's clock.
Cut and download
Press Cut clip and download the MP4. You can cut several clips from the same video.

Video trimmer: details

Input: MP4, MOV, MKV and AVI videos, Dahua .dav recordings and Hikvision exports
Output: .mp4 with the original video stream
Quality: Unchanged; the video is copied, not re-encoded
Accuracy: Times are exact to the millisecond. The clip starts at the keyframe at or before your start time, often a second or two earlier, because a lossless cut can only start on a keyframe. It ends after the last frame that starts before your end time; with B-frames that can be a frame or two later, and the row says where
Audio: AAC and MP3 are copied; other audio, such as G.711 from CCTV, is converted to AAC
Recording time: Kept: each clip's creation date is the source's recording time plus where the clip really starts, and CCTV clips are named by the recorder's clock, like 2019-02-13_19-24-22_to_19-24-24_CH01.mp4
Location: Left out of every clip; the recording date is kept
Upload: None; the video is cut in your browser
Price: Free

Video trimmer: questions

How do I trim a video without losing quality?

Copy the part you need instead of re-encoding it. In tuul's video trimmer you open the video, set the start and end, and press Cut clip: that part of the video stream is copied as it is, so the picture is identical to the original and even long recordings take seconds.

Why does my clip start a little earlier than I chose?

Videos store a full picture, called a keyframe, only every second or few seconds; the frames in between only record what changed. A lossless cut has to start on a keyframe, so the clip begins at the last keyframe before your start time. The clip's row tells you exactly where it starts.

Can I trim CCTV footage?

Yes. Dahua .dav recordings and Hikvision .mp4 exports are converted to MP4 on your device first, then cut. Each clip is named by the recorder's clock at its real start and end, and that time is saved as the clip's creation date, so clips sort by when they happened. When you share a clip, leave a second or two either side of the moment, and keep the original recording too.

Is my video uploaded?

No. The cutter downloads once to your browser and runs on your device, so the video never leaves your computer or phone.

Can I cut several clips from one video?

Yes. After each cut, change the start and end and press Cut clip again. Each clip gets its own row and download button.

Why is there no preview?

Your browser can't play the video's codec, usually H.265 (HEVC). You can still type the start and end times. The cut works the same way, and the clip plays in apps that support H.265, such as VLC.

Is there a size limit?

The tool sets none. Very large files can run out of memory on phones, so for videos over about 1 GB a computer is more reliable.

Next steps

Video to MP3Take the sound out of any video, CCTV too, as MP3.

Guides

How to get the audio from a video (MP4 to MP3)Save the sound of an MP4 or MOV video as MP3 or M4A. Which bitrate to pick, MP3 vs M4A, the built-in ways on Mac and Windows, and a free converter.
Hikvision MP4 won't play or has no soundWhy Hikvision, HiLook and EZVIZ .mp4 exports won't open, play without sound or show no picture, and how to fix each one without re-encoding.
How to play DAV files on Mac, PC and phonePlay Dahua .dav CCTV recordings on Windows, Mac, iPhone and Android with Smart Player or VLC, or convert them to MP4 in your browser.
How to make a video small enough to sendWhatsApp, Discord and email size limits for videos, and three ways to fit under them - cut it, send it as a document or link, or shrink it.
What is a DAV file and how do you open it?DAV is the recording format of Dahua CCTV recorders. Here's what's inside a .dav file, why normal players can't open it, and three ways to watch it.