Road bike size guide - picture of cannondale synapse road bike

Road Bike Size Guide

Use our road bike size guide to find the perfect size for you. Choose the right size road bike and you’ll be more comfortable and more efficient, so you can go quicker, especially over longer distances.

It’s simple to work out the right road bike size for you. All you need is:

1. Your height & 2. Your inside leg length

Then, use the size charts below to match your measurements to the manufacturers recommended frame size

Browse Road Bikes By Size

Road bike sizing chart (Men)

Height Inside leg Men's road bike size
147cm-152cm / 4'10"-5'0" 66cm / 26" 47, 48cm (XX Small)
152cm-160cm / 5'0"-5'3" 69cm / 27" 49, 50cm (X Small)
160cm-170cm / 5'3"-5'7" 71cm / 28" 51, 52, 53cm (Small)
170cm-175cm / 5'7"-5'9" 76cm / 30" 54, 55cm (Medium)
175cm-180cm / 5'9"-5'11" 79cm / 31" 56, 57, 58cm (Large) (Giant – ML)
180cm-188cm / 5'11"-6'2" 81cm / 32" 59, 60cm (X Large)
188cm-196cm / 6'2"-6'5" 86cm / 34" 60, 61, 62cm (X Large, XX Large)
196cm+ / 6' 5"+ 91cm / 36" 62, 63cm (XX Large)

Road bike sizing chart (Women)

Height Inside leg Women's road bike size
147cm-155cm / 4'10"-5'1" 66cm / 26" 44, 45, 46cm (XX Small)
155cm-160cm / 5'1"-5'3" 69cm / 27" 47, 48, 49cm (X Small)
160cm-165cm / 5'3"-5'5" 71cm / 28" 50, 51, 52cm (Small)
165cm-172cm / 5'5"-5'8" 76cm / 30" 53, 54, 55cm (Medium)
172cm+ / 5'8"+ 79cm / 31" 56, 57cm (Large)


How do I measure my height?

With your shoes off, stand upright against a wall, with your shoulders back and legs together. Use a pencil to make a small mark on the wall above your head – make sure you hold the pencil parallel to the floor. Then measure from the floor to your mark, in centimetres or feet and inches.

How do I measure my inside leg length?

With your shoes off, stand upright with your back against a wall. Place a book/ruler between your legs, level with your crotch. Then measure from the floor to the top of the book/ruler, in centimetres or feet and inches (it’s easier if a friend helps).

How are Road Bikes Sized?

Road bikes are usually sized in centimetres, or using a S/M/L system. A road bike’s frame size is traditionally calculated by measuring the length of the seat tube, from the top of the tube (where the seat post inserts), to the centre of the front chainring. To keep sizing consistent across models, Compact road bikes (with a sloping top tube) are either sized using a S/M/L system, or are sized with a ‘virtual’ seat tube measurement based on a traditional (non-compact) frame. NB. Sizes can vary slightly between manufacturers.


Road Bike Size FAQs

The height of your saddle is a crucial indicator of road bike size. Using the LeMond formula, you may roughly calculate this by multiplying your inside leg length by 0.885. You may also test it empirically by adjusting your saddle such that your straightened leg can rest in the middle of the pedal.

The frame is probably too big if you have trouble turning or have to sit up straight to reach the handlebars. You might also observe that your larger body and the way you sit prevent you from turning or picking up pace rapidly. The frame is too big for you if it causes you pain or discomfort after riding.

Choose a larger frame if your arm span exceeds your height. Get the smaller one if it's shorter. The reach to the handlebars will be longer on a larger bike. You may feel more at ease on a larger frame if your arms are proportionately longer.

When riding a road bike, specifically, riding a frame that is the improper size will eventually cause lower back pain. A seatpost or handlebar adjustment won't make up for the frame. Choosing a bike that is ideal for your size will help you pedal more effectively.

Other Size Guides

Nik Hudson