How to Change Video Aspect Ratio of MP4, AVI, MKV, WMV, MOV, WebM, etc?

Easily Change Video Aspect Ratio of MP4, AVI, MKV, WMV, MOV, WebM, etc among 16:9, 4:3, 2.35:1, 1.85:1, etc

Aug 28, 2014, Posted by Shirley White


The aspect ratio describes the proportional relationship of the video image between its width and its height. It is commonly expressed as two numbers separated by a colon, as in 16:9. Two common videographic aspect ratios are 4:3 (1.33:1), the universal video format of the 20th century, and 16:9 (1.77:1), universal for high-definition television and European digital television.

16:9 (1.77:1) (16:9 = 42:32) is an aspect ratio with a width of 16 units and height of 9. Since 2009, it has become the most common aspect ratio for sold televisions and computer monitors and is also the international standard format of HDTV, Full HD, non-HD digital television and analog widescreen television.

4:3 (1.33:1) is an aspect ratio with a width of 4 units and height of 3. It is for standard television and has been in use since the invention of moving picture cameras and many computer monitors used to employ the same aspect ratio.

There are many other aspect ratios like 1.85:1, 2.39:1, 5:3, 5:4, and 1:1.

How to Change Aspect Ratio of Video?

To change aspect ratio of the source video to your desired one, you need a professional Video Aspect Ratio Changer - Faasoft Aspect Ratio Changer which enables to change video aspect ratio among 4:3, 16:9, 2.35:1, 1.85:1, 1:1, 21:9 etc.

Key Features of Faasoft Aspect Ratio Changer:

  • Change Aspect Ratio of almost all kinds of video formats like change MP4 aspect ratio, change AVI aspect ratio, change YouTube aspect ratio, change MKV aspect ratio, change WMV aspect ratio, change MOV aspect ratio, change WebM aspect ratio, change FLV aspect ratio, change video aspect ratio of ASF, WTV, MVI, AVCHD, 3GP, OGV, MXF, etc;
  • Change aspect ratio meanwhile keep the source video format; Adjust aspect ratio meanwhile convert video to other formats;
  • Support almost all kinds of video and audio formats like WTV, WMV, ASF, ASX, AVI, XMV, DV, HDV, DV-AVI, DivX, Xvid, MKV, FLV, F4V, SWF, MXF, MVI, OGM, WebM, MP4, 720p/1080p AVCHD, MTS, TOD, MOD, TP, Apple ProRes, OPUS, AAC, AC3, DTS, ALAC, OGG, OGA, MP3, WAV, FLAC, WMA, 3GA, M4A, M4B, APE, AU, AIFF, AIFC, CAF, MPC, QCP, VOC, VOX, GSM, etc.

Change Aspect Ratio with Faasoft Aspect Ratio Changer

Free download and install the powerful Faasoft Aspect Ratio Changer, and then follow the step by step guide to adjust video aspect ratio. Here we take changing MP4 aspect ratio as example.

Step 1 Add MP4 files to Faasoft Aspect Ratio Changer
Simply drag and drop MP4 to the main interface of Faasoft Aspect Ratio Changer, and the file will be loaded immediately.

Step 2 Change MP4 aspect ratio
After the MP4 file is loaded, click "Settings..." button of the program to go to "Advanced" tab. Then click the "+" on the left of the "Video Codec" to expand the video parameter group.

Click the Auto drop down button of "Aspect Ratio" to select 4:3 or 16:9 or just enter your desired one like 2.35:1, 1.85:1, 1:1, and etc. And then click "Apply to All" and OK.

Step 3 Start changing aspect ratio
After all set done, click "Convert" button of Faasoft Aspect Ratio Changer to start changing aspect ratio of video.

Tips: Set output format before conversion

Click the drop-down button of "Profile" to select the output formats as you want.


It is easy to change video aspect ratio on Windows or Mac with the above full guide! And you will never worry about the following situations:

  • I have a bunch of downloaded .mp4 files that, for some reason, are in 16:9 while the original material was in 4:3. I want to put these on a Zune, and the Zune can't stretch video. So I'm looking for a way to change it. Thanks.
  • Any way I can have the display set to 4:3 instead of 16:10 aspect and not use all the screen width?
  • Does anyone know any good software for manually changing the aspect ratio/resizing of video files?
  • I have a 480x360 video clip from broadcast TV that was originally 16:9 aspect ratio but is now obviously squeezed to 4:3. I want to convert this such that it is 16:9 (480x320).
  • I sometimes get .mp4 and other video formats whose aspect ratio is clearly off
  • What apps do you use to reconvert such videos to an aspect ratio better suited to to fit either a regular desktop or LCD screen size?
  • I have a video clip (.avi) that is 16x9 but plays back squished into a 4x3 view (everyone is too tall and skinny). Is there any free software that will stretch this back out to the original 16x9?