How to convert a video to thebest format

[dalipksaini]

Hello,
will you please tell me the best way to convert my existing video files to the best format maintaining the file size.

 

[wilson1987]

Would you please provide us more detailed information?
What format is your video?

 

[truegenius]

use handbrake video converter
set resolution manually and set quality to around 22 to get best quality but minimum file size