How to Convert Video Files on Windows & Mac
Updated August 31, 2026
Video formats are mostly containers around similar innards, which means conversion is usually about compatibility, not quality: making the file your TV, editor, or upload form will accept.
ConvertSave converts between all the common containers with one drag-and-drop flow on Windows and Mac, locally and offline, which matters when files run to gigabytes.
How to convert any video file
- 1
Drag your files into ConvertSave
Open ConvertSave and drag your video files into the window. You can drop one file or a whole selection at once. There is no upload step, because the files never leave your computer.
- 2
Choose MKV as the output format
Pick MKV from the format list. ConvertSave shows the formats that make sense for the files you dropped, so MKV is right there.
- 3
Click Convert
Hit the Convert button. Each MKV file is saved next to the original, so you don't have to hunt through folders to find your converted files. The originals are left untouched.
Which video format should you pick?
| Format | Pick it for |
|---|---|
| MP4 | Playing and sharing anywhere; the safe default |
| MOV | Apple editing workflows |
| MKV | Recording and archiving with many tracks |
| WEBM | Embedding video in web pages |
| AVI | Legacy Windows software |
The busiest directions have dedicated guides: convert to MP4, MOV to MP4, MKV to MP4, WEBM to MP4, AVI to MP4, and convert to WEBM. Quality, resolution, and frame rate are adjustable in the advanced panel for any of them.
Converting to MOV
Old iMovie and Final Cut workflows sometimes want MOV specifically. Any of the common formats converts to it with the usual three steps.
Converting to AVI
The reverse of the usual migration, needed when legacy software or hardware only reads AVI. It's in the same output list as everything else.
Batch converting video
Queue any mix of formats and convert them to one output in a single pass; each file saves next to its source. We've tested batches of up to a thousand files.
Is video conversion safe?
The risk with converting your videos isn't the conversion itself, it's where the conversion happens. Free converter websites work by uploading your file to someone else's server. You usually can't tell who runs the server, where it is, or how long your file sticks around after the conversion finishes. For personal videos and photos that's a real privacy trade, and it's the reason so many of those sites are covered in aggressive ads.
ConvertSave does the conversion on your own computer. Nothing is uploaded anywhere. You can turn off Wi-Fi entirely and it still works, which is also the easy way to verify the claim. Your original file is never modified, and the converted copy is written right next to it.
Frequently asked questions
Does converting between containers lose quality?
The conversion re-encodes at defaults chosen to look identical in normal viewing, and the advanced panel hands you the quality controls when you want them.
Which format plays on everything?
MP4. When in doubt, convert to MP4.
Can I also extract just the audio?
Yes. Pick MP3, WAV, or another audio output instead of a video one; the video to MP3 guide covers it.
Do my videos get uploaded anywhere?
No. Conversion runs on your computer and works offline, with no multi-gigabyte uploads.
Is ConvertSave free?
There's a 7-day free trial with all features unlocked. After that it's $9/month, $60/year, or $129 once for a lifetime license that covers 3 personal devices on Mac and Windows.
