The most common question I get is “what frame size should I buy?"
The common answer you'll get from your local bicycle retailer will be “you look around a medium or a large”. If you're buying a modern high-performance bike, it's a good idea to be a bit more specific.
What is a medium?
If I asked somebody this question I would most likely get the answer 54cm or 56cm and they would be correct. But there's often confusion over where the 54 or 56 measured? More importantly, there's many more measurements you need to consider.
how to get your size right?
When it comes to getting the right sized bike, a millimetre is like a mile. A pre-purchase bike fit is an investment in buying the right bike.
Importantly, your bike fitter should draw you up your custom geometry so you can take this with you when you shop. If they're really helpful, they'll identify some bike brands that will suit you best.
Remember to plan before you buy, as this will insure lots of happy pain free riding and enjoyment