You can also go to www.caloriesperhour.com to get another estimate. I know the WebMD equations are accurate and so are calories per hour. The thing is, estimating calorie expenditure is not an exact science. For instance, biomechanical efficiency during activity, or ambient temperature, will affect the calorie expenditure (e.g., if you are an efficient swimmer you will burn fewer calories then someone whose strokes are poor and inefficient). But no calculator is smart enough to include those types of variables into the equation. If you get different estimates from two different reputable sites, then take the average. And again, consider that they are just estimates, and if you're estimating calorie intake for weight loss based partly on these estimates, then be sure to accommodate for any possible error. For example, if you figure your 24-hour energy expenditure (total number of calories you burn all day, including exercise and resting metabolic rate and dietary thermogenesis) is 2000 and you consume 1500 calories, then theoretically you should lose one pound per week (500 calorie deficit each day). But if you aren't losing weight, then there's error in your estimate of your calorie intake, calorie expenditure, or both. I hope that helps.

Rich