DIN on Rossignol FKS 140 for 5"8.5" 125lb

Go to a ski shop and have a tech do it. They have a chart that will put it at the right spot and will have the bindings checked to make sure they're actually releasing at that DIN.

need your boot soul length? Numbers printed usually on the heel of the boot. (not your foot size)
also need to say if you're type 1, 2 or 3 skier? (1= beginner, 2=intermediate, 3= advanced)

I am a certified ski tech

If you're only 125 lbs., I'd start at a 6 to be conservative. I ski hard and am your size but 140 lbs, and ski at an 8 for park.

If you start ejecting way too much (when you shouldn't be), then put them up to a 7. If you don't know what you're doing just go to a shop to get them dialed in right.

Also, you should have just gotten 120's if you're skiing at that low of a din.

SimplyCleanIf you're only 125 lbs., I'd start at a 6 to be conservative. I ski hard and am your size but 140 lbs, and ski at an 8 for park.

If you start ejecting way too much (when you shouldn't be), then put them up to a 7. If you don't know what you're doing just go to a shop to get them dialed in right.

Also, you should have just gotten 120's if you're skiing at that low of a din.

This. I weigh 165 and ride on a 9 in the park. And the 120 FKS are a cheaper buy for a binding that would work perfectly for you