How to Properly Size a Bike

Determining the Right Size Bicycle for You

Mechanic, salesman and client in a custom-made bicycle store
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Buying a bike isn't just about color or price. With so many styles and features available, buying a bicycle can be as complicated as buying a car, and considering the investment, you don't want to choose the wrong size. When looking for a new bike, consider whether you want a road bike, a mountain bike or a hybrid as sizing for each style is slightly different. Know your height and inseam measurement when determining what bike fits you, and don't forget to test ride any bike you consider.

Sizing Road Bikes

Female triathlete riding bicycle on street
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Road bikes are built for speed and distance, with light, strong frames and narrow, smooth tires designed for paved surfaces. Road bikes allow riders to lean far forward​ and grip the curved handlebars below as they hunch over, allowing for an aerodynamic ride that maximizes speed. Parts of higher end road bikes are made from lighter materials, such as carbon or titanium, and often have clips to attach riders to the pedals. When used for racing, a proper size is important, as an ill-fitting bike won't maximize a rider's speed.

Sizing Mountain Bikes

Mountain bikers descend trail with speed
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Mountain bikes are designed for rugged terrain and have wider, more upright frames. The wide tires allow a rider to traverse rocky, bumpy trails, and the tough rims and spokes are designed to withstand off-road elements. With straight, flat handlebars, mountain bikes are meant to be ridden upright for maximum control and road vision. The high upright frame also allows riders to avoid the rocks, logs, and other obstacles often found when riding in wooded areas or on trails.

Sizing Hybrid Bikes

Legs of a young businesswoman on a bicycle
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Hybrids combine characteristics of road bikes with features of mountain bikes to allow riders a comfortable, quick ride on streets and bike paths. These bikes are a good choice for a commuting bike​ when both speed and durability are desired. Not typically used for racing, hybrid bikes typically have straight, flat handlebars, and offer the thicker tires and stouter frame of a mountain bike, but also combine lighter components such as rims with gears that are more comparable to road bikes.

The Right Bike for You

Once you've found the right bike for you—whether it's a road bike, mountain bike, or hybrid—it's time to determine what size bike you need. Use your height and inseam as a guide to figure out the size range of bike you need, but don't forget to check out the bike in person. Stand over the frame, adjust the seat and try the handlebars. Test ride different sizes and styles, either at a shop or from a friend, and don't hesitate to ask questions.