How accurate are online "calories burned" calculators?

NaurielR

I know that most calculators over estimate, but I was wondering if anyone knows by how much.

I don't have a HRM, and by what I've read on this site they are the most accurate way of measuring. Is there a general rule I can follow to determine how many calories I've *actually* burned, or will I just have to err more on the side of caution?

I've been using "mapmyrun.com" as a calculator. I'm 4'11", 115lbs. For a six mile run at about a 10:00 min/mile pace, the calculator says I burn just short of 500 calories. Does this sound accurate?

LaMujerMasBonitaDelMundo

I also rely on online calculators & MFP calorie burned figures since I can't afford to buy an HRM as of this time. I think that will depend on the person doing the exercise. The problem with most calculators is that they assume that the person is doing the exercises vigorously & so if one person does it at a moderate pace then the calculator becomes unreliable. The same goes to a person who has been doing the same exercise for quite sometime now that he is becoming more efficient at it.

Just to be sure, I suggest deducting 5 minutes from the total workout time to get a more accurate number. Its better to underestimate than overestimating it.

meerkat70

Naurie, the accuracy varies wildly. But at your weight and height, that estimated burn sounds more or less right to me for the distance travelled. The average is about 100cals per mile and given that you're lighter than average, I'd expect it to be lower.

ShaunMc1968

I use a Garmin HRM and my calories are generally higher than the online MFP Calculator suggests. If you deduct 5% then you will be close enough.