If you are looking for the best antivirus software then I have some best software which you can use to secure your system and safe browsing experience.
Malwarebytes works amazing live well at detecting and deleting viruses, malwares and trojans. It takes a little more time to scan but the scan is a little more thorough. Installing updates is a must for this software too You can use malwarebytes for Windows 10 too but Windows Defender works fine.
The best Antivirus is Norton360. My Norton makes it easy for you to set up your Norton protection, check our security status, and extend our protection
I am using Kaspersky Internet Security 2017 in my PC it is very good in detecting the threats from internet and from external devices as well when we connect to our PC.
So my vote goes to Kaspersky Internet Security 2017.
For free software, Avast (https://www.avast.com/en-us/free-antivirus-download) is great antivirus software. The only downfall is you have to register it once a year, but that's a minor hassle for great software that you don't have to spend any money on.
the best antivirus for me is emsisoft antimalware, have a good behavior detection, Its super light, Almost without feeling it when he work, Can work together with webroot secure anywhere without problems. 2 together antivirus joined,
One in the online cloud,
and the other resident installed completely on your pc.