How can I resize my pics to use as an avatar?

[Lud65]

I have plenty of pics I'd like to use for my avatar choice.
How can I resize them to the avatar size specifics?
I don't have a photobucket account and I don't want one.
Is there any website where I can do this?
Thanks.

[jamesvroy]

http://pixresizer.en.softonic.com/

[retrograde]

Microsoft Paint - use the "resize" command

[Lud65]

I'm on an iMac now.

Any ideas or tips on resizing pics on an iMac?
I'm still learning.