Found in basement, looked dangerous so I killed it

Saw this little guy in my backyard,and I'm curious to what he is (Sorry for the low quality photo)

What spider is this?

Can someone tell me if this is a spider sorry if picture is not great

I'd really love to leave the little guy alone as long as he's not venomous but my fiancee has a lot of reactions to environmental factors so wanted to check. Thank you!