I appreciate that this is not an easy question to answer because the amount of calories burned depends on so many factors, like weight, elevation etc.

Part of the reason why I'm taking up cycling is to lose weight and get fit. From past experience, what works for me is to use the Spark People website / app. It gives you a calorie range and a food and exercise tracker. Previously, when doing a lot of running and weights, I had a tendency to under eat and not eat enough protein because I didn't realise how much calories I had burnt and was estimating how much more I needed. Spark People was what made me realise that I needed to up my calorie intake and include snacks on runs (though I've heard that cycling has the opposite effect and makes you ravenous).

I was pretty fit and healthy as a result and that's where I want to get back to. I'd like to use the same method again because I know it works. So now I'm trying to figure out how to calculate calories burned when cycling outside and on a trainer.

I found an article that gives rough estimates.

http://www.livestrong.com/article/13...king-one-mile/

And also a pretty intricate calculator, which seems a too much for what I need.

http://bikecalculator.com/tripUS.html

What does anyone else in a similar position do?

Also, does time on a trainer count for more than on a ride outside - purely on a fitness level (not technique obviously) - because you can't freewheel? Does this affect the calories burned calculation?