Why Is My Trimmed Video Bigger Than the Original (and How to Shrink It)

Your trimmed video is bigger because the editor didn't just cut it: it re-encoded the whole clip with its own export settings, usually a higher bitrate, a higher resolution or frame rate, or a less efficient codec than the original. File size depends on how many bits are spent per second of video, not only on length, so a 20-second clip exported at a generous setting can easily outweigh the 60-second original. Here is how to tell what happened and how to get the file small again without making it look worse.

Why trimming can make a video larger

When a phone camera records, it already balances size and quality. Many editing apps then throw that balance away on export:

• Higher bitrate. Export presets often aim for "high quality" and spend far more data per second than the original used.
• Upscaled resolution or frame rate. Exporting a 1080p clip as 4K, or 30 fps as 60 fps, adds size without adding real detail.
• Codec change. Recent iPhones record in HEVC (H.265), which is more efficient than H.264. An editor that exports H.264 at the same quality needs more data to do it.
• The original was already heavily compressed. Videos saved from messaging apps are squeezed hard. Re-exporting them at a normal bitrate makes them bigger, but can't bring back the detail that was lost.

Make the trimmed clip small again

Compress Video re-encodes the clip into an H.264 MP4 of up to 1280p, which is plenty for phones, chats and most uploads. It runs in your browser and the file is not uploaded.

1. Open Compress Video and drop your MP4, MOV, WEBM, MKV, AVI or M4V file on the page, or click to browse. You can add several at once.
2. Adjust the quality if you like, then click Compress. Everything happens on your device.
3. Download the MP4 file. If it is still too big, or looks too soft, change the options and run it again on the same file.

Compare the new size with both the trimmed export and the original before you delete anything. If you need to keep a 4K clip at full resolution, this tool isn't the right fit, because its output tops out at 1280p.

Trim with fewer surprises next time

Filevale doesn't trim or edit videos, so do the cutting in the editor you already have and check its export settings:

• On iPhone, open the video in Photos, tap Edit, drag the yellow handles, then tap Done and save it as a new clip so the original stays untouched.
• On a Mac, open the video in QuickTime Player and choose Edit → Trim.
• In a third-party editor, look for the export resolution, frame rate and quality settings, and match them to the original instead of picking the highest preset.

On iPhone, the Filevale iPhone app also has a compressor that works straight from your Photos library (HEVC), which is the easiest route there. The browser tool above is the no-install alternative.

If something else is the problem

• The file is a MOV that won't play or upload elsewhere. Turn it into MP4 with MOV to MP4, or pick another output in Video Converter.
• You only need the sound. Video Converter can save the clip as MP3, M4A or WAV, which drops the video track entirely.
• You want a short loop for chat. Video Converter also outputs GIF and WebM. GIFs of long clips get big quickly, so keep them short.
• You have photos, PDFs and videos to shrink at once. Reduce File Size gathers the shrinking tools in one place.

For size targets like email, WhatsApp or Discord, see how to reduce video file size. On a Mac, compressing a video on Mac covers the built-in options.

Frequently asked questions