The fastest way to convert a video to MP4

You can convert a video to MP4 using free software on your computer, an online converter, or a video editor you may already have installed. The method depends on what device you're using, how many videos you need to convert, and whether you want to change the video quality or size while converting.

MP4 is the most widely supported video format — it plays on phones, tablets, computers, and most streaming devices without extra software. If you have a video in a different format (like MOV, AVI, WMV, or MKV), converting it to MP4 makes it easier to share and watch anywhere.

Key Takeaways

  • Windows computers come with the Photos app, which can convert videos to MP4 without downloading anything extra.
  • Mac users can use QuickTime Player to convert MOV files to MP4, or download free software like HandBrake for other formats.
  • Online converters work on any device but upload your video to someone else's server, so avoid them for private or sensitive videos.
  • HandBrake is free, works on Windows, Mac, and Linux, and lets you shrink file size or change quality before converting.
  • The conversion process takes longer for large files — a 1 GB video may take 10 to 30 minutes depending on your computer's speed.

Convert video to MP4 on Windows using the Photos app

The Photos app comes built into Windows 10 and Windows 11, so you do not need to download anything. Open the Photos app, find the video file you want to convert, and use the trim and edit tools to export it as MP4.

Open the Photos app and navigate to the folder where your video is stored. Click on the video to open it, then click the three-dot menu button in the top right corner. Select "Edit and create" and then "Trim" or "Edit" — you do not have to actually trim or edit the video, but opening this menu lets you export it. Click the "Save as" button at the top, choose "Video MP4" from the dropdown menu, and click "Export." Windows will save the converted file to your Videos folder.

This method works best for videos already close to MP4 format. If your video is in an older format like AVI or WMV, or if you want to reduce the file size, use HandBrake instead.

Convert video to MP4 on Mac using QuickTime Player

If your video is already in MOV format (the native Mac format), QuickTime Player can convert it to MP4 in seconds. Open QuickTime Player, go to File > Open File, select your MOV video, then go to File > Export As and choose "MP4" from the format dropdown.

For videos in other formats like AVI, WMV, or MKV, QuickTime Player will not work. Download HandBrake instead — it is free, works on Mac, and handles almost any video format. Open HandBrake, drag your video file into the window, make sure "MP4" is selected under "Container" on the right side, and click "Start Encode." The converted file will appear in the same folder as your original video.

Use HandBrake to convert any video format to MP4

HandBrake is free software that works on Windows, Mac, and Linux. It converts almost any video format to MP4 and lets you reduce file size or change video quality before converting. Download it from handbrake.fr — avoid other websites claiming to offer HandBrake, as they may contain unwanted software.

After installing HandBrake, open it and click "Open Source" to select your video file. On the right side under "Container," make sure "MP4" is selected. Leave the other settings as they are unless you want to change them — the default settings work for most videos. Click "Start Encode" at the top right and wait for the conversion to finish. The converted file will be saved in the same folder as your original video, with "MP4" added to the filename.

If you want to reduce file size, click the "Quality" dropdown and select a lower number — lower numbers mean smaller files but slightly lower picture quality. If your original video is very large (over 2 GB), reducing quality can cut the file size in half. The conversion will take longer with larger files; a 1 GB video typically takes 10 to 30 minutes depending on your computer's processor speed.

Convert video to MP4 using an online converter

Online converters like CloudConvert, Zamzar, or Online-Convert let you convert video without downloading software. Go to the website, click "Select File," choose your video, select MP4 as the output format, and click "Convert." The website will convert your video and let you download the MP4 file.

Online converters are convenient if you only convert videos occasionally or if you cannot install software on your computer. However, your video file is uploaded to someone else's server during the conversion, so do not use online converters for private videos, medical records, or anything sensitive. Also, free online converters often have file size limits — most will not convert videos larger than 500 MB to 1 GB.

If you use an online converter, check the website's privacy policy to understand what happens to your file after conversion. Most delete files after a few hours, but some may keep them longer.

What to do if your converted video will not play

If your new MP4 file will not play on a device, the problem is usually the video codec — the compression method used inside the MP4 file. MP4 is a container format that can hold different types of video inside it, and not all devices support all types.

The most compatible codec for MP4 is H.264 video with AAC audio. If your converted video will not play, re-convert it using HandBrake and look for a preset called "Fast 1080p30" or "General" — these use H.264 by default. If you converted using an online tool, try a different converter, as different tools use different codecs.

On a phone or tablet, try opening the video in a different app — the default video player may not support the codec, but another app might. On a computer, try VLC media player (free, works on Windows and Mac), which plays almost any video format.

Batch convert multiple videos at once

If you have many videos to convert, HandBrake can convert them one after another without you watching. Open HandBrake and click "Open Source" to select your first video. Set up the conversion settings (make sure MP4 is selected), then instead of clicking "Start Encode," click "Add to Queue." Repeat this for each video you want to convert, then click "Start Encode" once — HandBrake will convert all of them in order.

Batch conversion takes a long time — if you have 10 videos of 1 GB each, the process may take several hours. Start the batch conversion before you leave your computer, or do it overnight. Your computer will need to stay powered on and awake during the entire process.

Frequently Asked Questions

How long does it take to convert a video to MP4?

Conversion time depends on your computer's speed and the video's size and quality. A 500 MB video typically takes 5 to 15 minutes. A 1 GB video takes 10 to 30 minutes. Older computers or videos with high quality settings take longer. Online converters may be faster or slower depending on the website's server speed.

Will converting to MP4 make the video smaller?

Not automatically — MP4 is just a container format. The file size depends on the video codec and quality settings you choose. HandBrake lets you reduce quality to shrink the file, but the Photos app and QuickTime Player keep the original quality. If you want a smaller file, use HandBrake and select a lower quality setting.

Can I convert a video on my phone?

Yes, but it is slower and more limited than on a computer. On iPhone, use the Photos app to trim and export videos as MP4. On Android, apps like VidCompressor or MediaConverter can convert videos, though they work best for smaller files. For large videos or many conversions, a computer is faster and more reliable.

What if the video is protected or has copy protection?

Videos with copy protection (like movies from streaming services) cannot be converted using these tools — the software will refuse to open them. This is intentional and legal. You can only convert videos you own or have permission to convert.

Do I need to delete the original video after converting?

No — the original stays on your computer. You now have two copies: the original in its old format and the new MP4 version. Delete the original only if you need to free up storage space and are sure you do not need it anymore.