Burning calories on treadmill????

Hi all...im new to posting here.....i mostly lurk...but i LOVE THIS BOARD!!! Anyway....my question is... i have been walking on the treadmill for 30 minutes each day...i enter my weight...and at the end of my work out it shows how many calories i have burned....does anyone know if that is really accurate?? I just wondered if there is a "formula" to figure out burned calories?? Thanks for any answers....you guys are GREAT

Kathleen, I think it depends on if you are in the range of "normal weight"... for example, there is a basic formula for how many calories it takes to sustain X weight... well... I figured out that I needed to eat something like 15,000 calories a day based on this "scientific formula" to maintain my weight... and in all honestly I was probably eating about 3,000 calories in the average day and gaining weight. I don't know if that helps or not but I would say be cautious as our bodies as SMO folks are way out of wack from the "norm". Patti