How many calories do you burn in 10 km?

I'm no expert but I am a runner and a nutrition savvy person. I know that every person burns calories different depending on weight, height, % muscle, BMR, hormones, etc.

I found from an unreliable source this factor: 0.653 calories/mile/pound which is likely an average over a population.

multiply your weight (in pounds) by the distance (in miles) and this factor and you should get an idea.

e.g.: I am 122 pounds so if I run 10K (6.213 miles) i will have burned 495 calories. This sounds about right as I usually get a reading of 590 calories on a treadmill for a 10K (and treadmill calorie counters aren't reliable in my opinion.