Determining Road Bike Frame Size and Saddle Height

Getting the correct frame size is one of the most important parts of bicycle selection. Getting the right frame size is the starting point to correct bike fit, ensuring the bike will be comfortable and efficient to ride. The old-fashioned way to check for “proper” frame size that some still use is to straddle the bike, making sure there is about an inch or so between the top tube and your crotch. Luckily, there is a formula for determining frame size that is easy to use and yields good results.

Known as the LeMond sizing method, It was originally used by American racing cyclist and Tour De France champion Greg LeMond.

To find your frame size and saddle height:
Measure your inseam length by standing in your stocking feet on a flat surface against a wall. Firmly place a book (approximately 2 inches thick, not an encyclopedia) up to your crotch with one edge of the book against the wall. Have a helper draw a line where the top of the book touches the wall. Measure the distance from the floor to that mark. This is your inseam length measurement.

Refer to the chart below to find your frame size and saddle height.

Inseam Length		Frame Size		Saddle Height
Inches	cm	Inches	cm	Inches	cm
26.0	66.0	16.9	42.9	23.0	58.3
26.5	67.3	17.2	43.8	23.4	59.4
27.0	68.6	17.6	44.6	23.8	60.6
27.5	69.9	17.9	45.4	24.3	61.7
28.0	71.1	18.2	46.2	24.7	62.8
28.5	72.4	18.5	47.1	25.2	63.9
29.0	73.7	18.9	47.9	25.6	65.0
29.5	74.9	19.2	48.7	26.0	66.2
30.0	76.2	19.5	49.5	26.5	67.3
30.5	77.5	19.8	50.4	26.9	68.4
31.0	78.7	20.2	51.2	27.4	69.5
31.5	80.0	20.5	52.0	27.8	70.6
32.0	81.3	20.8	52.8	28.3	71.8
32.5	82.6	21.1	53.7	28.7	72.9
33.0	83.8	21.5	54.5	29.1	74.0
33.5	85.1	21.8	55.3	29.6	75.1
34.0	86.4	22.1	56.1	30.0	76.3
34.5	87.6	22.4	57.0	30.5	77.4
35.0	88.9	22.8	57.8	30.9	78.5
35.5	90.2	23.1	58.6	31.3	79.6
36.0	91.4	23.4	59.4	31.8	80.7
36.5	92.7	23.7	60.3	32.2	81.9
37.0	94.0	24.1	61.1	32.7	83.0
37.5	95.3	24.4	61.9	33.1	84.1
38.0	96.5	24.7	62.7	33.6	85.2
38.5	97.8	25.0	63.6	34.0	86.3
39.0	99.1	25.4	64.4	34.4	87.5
39.5	100.3	25.7	65.2	34.9	88.6
40.0	101.6	26.0	66.0	35.3	89.7
40.5	102.9	26.3	66.9	35.8	90.8
41.0	104.1	26.7	67.7	36.2	92.0
41.5	105.4	27.0	68.5	36.6	93.1
42.0	106.7	27.3	69.3	37.1	94.2
42.5	108.0	27.6	70.2	37.5	95.3
43.0	109.2	28.0	71.0	38.0	96.4
43.5	110.5	28.3	71.8	38.4	97.6
44.0	111.8	28.6	72.6	38.9	98.7

Frame and Saddle Height Measurement

Determining Frame Height
Referring to measurement “A” in the diagram above, measure from the center of the crank spindle up the seat tube to the point where the center of the top tube meets the seat tube.

Determining Saddle Height
Referring to measurement “B” in the diagram above, measure from the center of the crank spindle along the seat tube to the top of the saddle. Adjust the saddle height to the measurement that corresponds to your inseam length on the frame size and saddle height chart above.

The saddle height from the chart is not set in stone. It will be close, but you may find after riding the bike for a while that you need to adjust the saddle slightly higher or lower than the measurement found in the chart. Keep in mind that an inch (2.54cm) of saddle height adjustment is huge. Try making smaller saddle adjustments and riding the bike for a while until you get the height that is right for you.