What is Best Minecraft Anticheat Free Version ?

MineSecure i think but Phoenix Anti-Cheat is very nice too

Im using "No Cheat Plus"
other:
Phoenix Anti-Cheat
WatchCat
AutoEye AntiCheat

AntiCheat was a good plugin for 1.8 but is no longer updated. It would detect all sorts of hacks on the fly beyond what NCP could ever do.

crack of AAC is good but you have to crack it and then configure it

cracked fiona v2 isnt bad i own a server that uses it and for the most part its hacker free

I dont play minecraft that much anymore but i have heard pac is really good

A lot of people make their own anticheats like watchguard and things like that.

NCP, AAC, PAC, WOLF, AntiCheat, AntiCheat+... Google, u might find more

AAC is really good but it costs money unless you know where to find it

NoCheatPlus is definitely the best. You can tweak it a lot. There's some configurations you can find online, as well as addons that were designed specifically for it.