The short answer
Add the AVI, choose an MP4 output profile, check the video and audio settings and convert to a separate folder. MP4 is a container; the codecs inside it also affect whether a device can play it.
Add and inspect the AVI video
Open CyberPower Video Switch and add your AVI file. Check its duration and audio. If the input does not play correctly, converting it is not a guarantee that a damaged or unsupported stream can be repaired.
Choose an MP4 output for the destination
Select a supported MP4 profile. For a player that accepts H.264 video and AAC audio in MP4, choose a matching profile and review those settings. Do not assume that every device accepts every codec inside an .mp4 file.
Keep the source dimensions and frame rate unless you need a specific output. Increasing the resolution cannot add detail to a low-resolution AVI. File size depends on duration, codec, bitrate and other settings; MP4 does not automatically mean a smaller file.
Review, convert and check sync
Choose Save to and an output folder separate from the source. Start Convert and wait for the job to finish. Check the MP4 in your intended player, including the beginning, end and whether voices remain in sync with the picture.
For other source or output formats, see the video conversion workflow. If you only need the sound from a video, use the audio extractor.
Download the free app
CyberPower Video Switch is free for its supported features. No subscription or paid activation is required.
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