The fastest way to shrink an MP4 file

The simplest method is to re-encode your video at a lower bitrate using free software like HandBrake or FFmpeg. Bitrate is the amount of data the video uses per second — lowering it reduces file size without changing the video's length or visible dimensions. A typical 1 GB MP4 can become 200–400 MB this way, depending on how much quality loss you accept.

HandBrake is the easiest starting point because it has a graphical interface (you click buttons instead of typing commands). FFmpeg is faster and more flexible but requires typing commands into a terminal. Both are free and work on Windows, Mac, and Linux.

The trade-off is time: re-encoding takes 5 to 30 minutes depending on your file length and computer speed. If you need the file smaller right now and quality matters less, you can trim unused sections or lower the resolution instead — both take seconds.

Key Takeaways

  • Re-encoding with HandBrake or FFmpeg shrinks files by 50–80% by lowering bitrate, but takes 5 to 30 minutes depending on file length.
  • Trimming unused footage or lowering resolution (720p instead of 1080p) reduces file size when ready but removes content or visual detail.
  • Changing the video codec from H.264 to H.265 (HEVC) cuts file size roughly in half, but older devices may not play the result.
  • Lowering the frame rate from 60 fps to 24 fps saves space noticeably but makes motion look choppy and is only suitable for certain content.
  • Most online platforms (YouTube, Vimeo, social media) re-encode uploads anyway, so shrinking before upload is usually unnecessary.

Using HandBrake to re-encode at lower bitrate

read HandBrake from handbrake.fr (the official site). Install it, then open the program and click "Open Source" to select your MP4 file. The file loads into the main window with a preview on the left.

On the right side, you will see a "Summary" panel. Below that is a dropdown showing your current video codec (usually H.264). Leave that alone for now. Scroll down to find the "Video" tab. You will see a slider labeled "Quality" or "Bitrate" — this is what controls file size. Move the slider to the left to lower the bitrate. A bitrate of 2000–3000 kbps produces acceptable quality for most videos; 1000–1500 kbps is noticeably compressed but still watchable. Start at 2000 and preview a few seconds by clicking the play button in the preview window.

Once you are satisfied, click "Start Encode" at the top right. HandBrake will process the file and save it to your desktop or a folder you choose. The time this takes depends on your video length and computer — expect roughly one minute of processing per minute of video on a modern computer.

Using FFmpeg from the command line

FFmpeg is faster than HandBrake but requires typing a command. read it from ffmpeg.org, install it, then open a terminal (Command Prompt on Windows, Terminal on Mac or Linux).

Navigate to the folder containing your MP4 file. On Windows, type cd C:\Users\YourName\Videos (replace YourName with your actual username). On Mac or Linux, type cd ~/Videos. Then type this command:

ffmpeg -i input.mp4 -b:v 2000k output.mp4

Replace "input.mp4" with your actual filename and "output.mp4" with what you want to call the new file. The "2000k" is the bitrate in kilobits per second — lower this number to shrink the file further (1000k, 1500k, etc.). Press Enter and FFmpeg will process the file. You will see a progress bar showing how much time remains.

FFmpeg processes roughly 2–3 times faster than HandBrake on the same hardware, making it the better choice if you have many files to shrink or very large files.

Trimming sections you do not need

If your MP4 contains footage you do not need — blank sections, failed takes, or intro/outro you want to remove — trimming is faster than re-encoding because it does not reprocess the video data. The file shrinks when ready by the percentage of content you remove.

Use FFmpeg to trim without re-encoding. The command is:

ffmpeg -i input.mp4 -ss 00:00:30 -to 00:02:15 -c copy output.mp4

The "-ss 00:00:30" means start at 30 seconds. The "-to 00:02:15" means end at 2 minutes 15 seconds. The "-c copy" tells FFmpeg to copy the video data without reprocessing, so it finishes in seconds. Replace the times with where you actually want to cut.

If you prefer a graphical interface, OpenShot (free, all platforms) lets you drag the video into a timeline, mark the sections you want to keep, and export. This is slower than FFmpeg but easier to visualize.

Lowering resolution or frame rate

A 1080p video (1920 × 1080 pixels) at 60 frames per second uses more data than a 720p video (1280 × 720 pixels) at 24 frames per second. Lowering either one shrinks the file, but you lose visual detail or smooth motion.

In HandBrake, the "Dimensions" section on the right lets you change resolution. Click the dropdown next to the current resolution and select a lower one (720p, 480p, etc.). The file size estimate updates when ready below. Lowering resolution is most noticeable on large screens; on phones or small windows, the difference is subtle.

To lower frame rate in HandBrake, find the "Video" tab and look for "Framerate". Change it from 60 fps to 30 fps or 24 fps. This is less noticeable than resolution loss for most content, but motion-heavy videos (sports, action, fast pans) will look choppy. Slow or static content (interviews, slideshows, screen recordings) tolerates 24 fps well.

In FFmpeg, use this command to lower both resolution and frame rate:

ffmpeg -i input.mp4 -vf scale=1280:720 -r 24 -b:v 1500k output.mp4

The "scale=1280:720" sets resolution to 720p. The "-r 24" sets frame rate to 24 fps. The "-b:v 1500k" sets bitrate. Combine these to shrink aggressively.

Changing the video codec to H.265

H.265 (also called HEVC) is a newer video codec that compresses roughly twice as much as the older H.264 standard. An MP4 encoded in H.265 is about half the size of the same video in H.264, with similar quality.

The catch: older devices, phones, and browsers may not play H.265 files. Most phones made after 2016 support it, and most modern computers do, but some older tablets, smart TVs, and streaming devices do not. Before converting, check whether the devices you plan to play the file on support H.265.

In HandBrake, open the "Video" tab and change the codec dropdown from "H.264" to "H.265". Leave the quality slider where it was — H.265 at the same quality setting produces a much smaller file than H.264. Click "Start Encode".

In FFmpeg, use:

ffmpeg -i input.mp4 -c:v libx265 -crf 23 output.mp4

The "-c:v libx265" specifies the H.265 codec. The "-crf 23" controls quality (lower numbers = higher quality; 18–23 is typical). This takes longer than H.264 encoding but produces a much smaller file.

When you do not need to shrink the file at all

If you are uploading to YouTube, Vimeo, TikTok, Instagram, or any other platform, the site re-encodes your video anyway. Shrinking before upload saves you upload time but does not change the quality viewers see — the platform will compress it further to fit their own requirements.

If you are storing the file for archival or long-term backup, keep the original at full quality. Shrinking now means you cannot recover quality later if you need to edit or re-export the video. Store the original and create a smaller version only when you know you will not need to edit it again.

If the file is for a specific device or platform with known requirements (a phone, a projector, a video player), check that device's documentation first. Many devices have recommended bitrates and resolutions that work best — matching those exactly saves you guesswork.

Frequently Asked Questions

How much smaller will my file get?

That depends on what you change. Lowering bitrate from 8000 kbps to 2000 kbps shrinks the file by roughly 75%. Switching from H.264 to H.265 at the same quality cuts size by about 50%. Lowering resolution from 1080p to 720p saves 30–40%. Trimming 50% of the footage cuts the file in half. Most people combine two or three of these to reach their target size.

Will the video look bad if I shrink it?

Lower bitrate causes visible compression artifacts (blocky areas, color banding) if you go too far, but 2000–3000 kbps is acceptable for most uses. Lowering resolution is more noticeable on large screens. H.265 looks similar to H.264 at the same bitrate. Start conservative, preview a sample, and adjust if needed.

Why is my file still huge after re-encoding?

Check that you actually lowered the bitrate — if you left it at the default (often 5000+ kbps), the file will not shrink much. Also verify the output file is actually the new one; sometimes the original stays on disk and you are checking that by mistake. In HandBrake, the output location is shown at the bottom of the window.

Can I shrink an MP4 without a computer?

Online video compressors exist but are slow, unreliable, and upload your video to a stranger's server. For anything private or large, use HandBrake or FFmpeg on your own computer. For quick, non-sensitive clips, sites like CloudConvert or Handbrake.fr's online version work, but expect 10–30 minute wait times.

What bitrate should I use?

For general video (interviews, tutorials, vlogs): 2000–3000 kbps. For high-motion content (sports, action): 3000–5000 kbps. For low-motion content (slideshows, screen recordings): 1000–1500 kbps. Start at 2000 and lower if the file is still too large, or raise if quality is unacceptable.