I am wanting to get a sanskrit tattoo on my biceps that says one life, one chance. But I don't know if the translation I'm getting is right. I've looked on sanskrit phrase websites and I've tried online translators but its all coming up different. I need help.

I don't want it to be wrong and have something other than what I want to say on my body forever!
The one I got off a sanskrit phrase site was एकं जीवनम्, एकः अवसरः