How do I convert a 20GB MKV file to a smaller x264 MP4?

[R.STEED]

How do I do it?! I currently use MakeMKV to rip the Blu Ray disc.

[ron spencer]

Handbrake

[redwudz]

Run it through a program like VidCoder. You will get some quality loss, how much depends on your settings.
I find VidCoder easier to use and more versatile than Handbrake. It uses the Handbrake engine.

[R.STEED]

What about converting MKV to MP4 using Nero video? Is that as good?

[sneaker]

No.

[R.STEED]

So what would be the setting for the best possible quality in Handbrake?

[sneaker]

Choose x264 encoder. Set "Preset" according to the encoding time you are willing to spend. "Medium" is a good start. Then set quality using "RF", "18" will give good quality (lower RF value = better quality = bigger file). Set "Profile" to "High". For BluRay you usually want to set "Framerate" to "Same as source" + "Constant Framerate". Audio tracks to "Auto-Pass Thru" to keep audio untouched.

Further info see the "technical documentation" on the HandBrake website.
https://handbrake.fr/docs/en/latest/

[R.STEED]

What produces the best quality....encoder set to fast or encoder set to slow?

[sneaker]

They can achieve the same quality but for a given quality fast will need more disk space.

[R.STEED]

This Handbrake is one helluva cool program. Thanks guys!

[R.STEED]

Why does it it say 'Warning' RF 0 is lossless if its set to zero?

[sneaker]

Lossless files will be extremely huge, larger than the original BluRay even. That's why it's warning you. Sane settings are in the range of 16 to 23. Start with 18 and decide if it's good enough.