How to Trim a Video in Dropbox (Step by Step)

You trim a video in Dropbox on dropbox.com, in your web browser. Log in, open the video from All files, click Edit at the top of the preview, set the part you want to keep, and click Save changes. It is available to all customers, so you do not need a paid plan. Dropbox's editor has limits, though: the file must be under 1 GB, shorter than 10 minutes, longer than 1 second, and lower than 4K resolution. Dropbox's help page does not claim trimming works in the mobile app, so use the website. If your video breaks one of those limits, or is not in Dropbox at all, the [Trim Video](/trim-video) tool on PixelTools is the fallback, and the last sections explain when to pick which.

Follow these steps on dropbox.com. First, log in to your Dropbox account in a web browser. Second, click All files and find the video. Third, click the video's name to open the preview. Fourth, click Edit at the top of the preview. Fifth, use the bar at the bottom of the player to set the clip: drag the start or the end of the clip until only the part you want is selected. Depending on the version of the editor you see, you may also choose to keep or delete a selection, so select the part you want and choose to keep or delete it. Sixth, click Save changes. Before you save, play the clip back once to confirm the start and end points are where you expect. Saving also involves a choice about the original file, which the next section covers.

When you save your trim, Dropbox gives you two choices: save a copy, or replace the original. Save a copy keeps your original video untouched and adds the trimmed clip as a new file. Replace the original overwrites the source with the trimmed version. If there is any chance you will want the cut footage back, save a copy. It costs a little extra storage, but it is the only option that lets you start over. Replace the original makes sense when the video is a throwaway, such as a quick screen recording you only need in short form, and you want to keep your folder tidy. Whichever you pick, you can only make the choice at the moment you save, so decide before you click.

Dropbox's editor only works on videos that meet all of these conditions: the file is under 1 GB, the video is shorter than 10 minutes and longer than 1 second, and the resolution is lower than 4K. The supported formats are MOV, MP4, M4V, MPG, MKV, MJPEG and AV1. If your file is a WebM or an AVI, those formats are not on the supported list. The 10 minute cap is the one people hit most often, because a full meeting recording or a long phone video is easily past it. A 4K clip from a recent phone can also be rejected on resolution alone, even when it is short. Check the file's size, length and resolution first, and you will know before you start whether the Dropbox editor can handle it.

Use Dropbox's own editor when your video fits its limits and you want the result to stay in Dropbox. There is nothing to download or re-upload, and you can replace the original in place if you want. One thing to know: Dropbox's help page does not specify whether trimming re-encodes the video, so we cannot tell you whether the output is identical in quality to the source. If exact quality matters for an important file, save a copy rather than replacing the original, and compare the two. Because the editor is free for all customers on dropbox.com, it is also the cheapest place to start before you reach for another tool.

If the video is over 10 minutes, over 1 GB, 4K, or a WebM or AVI, trim it with the [Trim Video](/trim-video) tool instead. Download the file from Dropbox, drop it into the tool, set the start and end, and export. It runs in your browser, so nothing is uploaded. It accepts MP4, MOV, WebM, MKV and AVI up to 2 GB, and we know of no duration cap. The tool seeks to the exact frame you pick, rather than the nearest keyframe. That is slower, because it decodes from the start of the file, but the cut is frame-accurate. You can then upload the short result back to Dropbox. This route also works for any video that was never in Dropbox, such as a file on your desktop.

PixelTools' trimmer always re-encodes. The output is an MP4 with H.264 video (CRF 23, veryfast preset) and AAC audio at 128 kbps, so the result is not bit-identical to your source. For most clips you will not notice, but it is a real difference from a tool that simply cuts the file. For sources whose long edge is over 2560 px, the output defaults to 1080p, because re-encoding 4K in a browser is slow and can produce corrupt frames when memory runs short. You can choose original, 1080, 720 or 480 instead. If your video is already inside Dropbox's limits and you want to avoid any extra re-encoding step on your side, use Dropbox's editor. If it is over a limit, the browser tool is the practical option, and it is honest about what it does to the file.