# How to Determine the Correct Frame Size for a Bike

When purchasing a new bicycle, be sure to take measurements and get the right fit. Just a push -- and a few numbers -- and you're on the way!

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#### You Will Need

• Wall
• Book
• Measuring tape
• Calculator
• Body type knowledge
• Test rides

## Steps

1. Step 1

Measure your inseam by standing barefoot with your back against a wall, looking straight ahead. Hold an inch-thick book between your legs. Measure the distance in centimeters from the top edge of the book to the floor.

2. Perform the measurement three or four times and calculate the average.

3. Step 2

Determine your measurement for a center-to-center measured road bike frame, which measures from the center of the bottom bracket to the center of the top tube, by multiplying your inseam by .65.

4. Step 3

Figure your measurement for a center-to-top measured road bike frame, which measures from the center of the bottom bracket to the top of the top tube or seat lug, by multiplying your inseam by .67. This accounts for the additional length of the top of the seat tube.

5. Step 4

#### Find your mountain bike size

6. Convert centimeters to inches by multiplying by .3937.

7. Step 5

Since women generally have longer legs and shorter torsos than men, women should look for frames with shorter top tubes or frames that are specially made for women. Men with shorter upper bodies or who prefer a more upright position should also consider frames with shorter top tubes.

8. Step 6