Trek Bikes SIze Guide
Trek Road Bikes
Madone, Emonda, Domane, Silque, Lexa, Boone, 1 Series
Frame Size | Height cm | Height Ft |
50cm | 157-165cm | 5.2-5.5 |
52cm | 163-170cm | 5.3-5.6 |
54cm | 167-176cm | 5.6-5.9 |
56cm | 173-180cm | 5.8-5.11 |
58cm | 179-187cm | 5.10-6.2 |
60cm | 183-192cm | 6.1-6.3 |
62cm | 189-197cm | 6.2-6.5 |
64cm | 194-201cm | 6.4-6.7 |
Trek Mountain Bikes
Top Fuel, Procaliber, Superfly, X-Caliber, Cali, Remedy, Fuel EX, Stache, Farley, Slash, Marlin, Roscoe
Frame Size | Height (cm) | Height (ft) |
XS | 148-155cm | 4.10-5.1 |
S | 153-163cm | 5.0-5.4 |
M | 161-173cm | 5.2-5.8 |
ML | 171-181cm | 5.7-5.11 |
L | 177-189cm | 5.9-6.2 |
XL | 187-197cm | 6.1-6.5 |
XXL | 197-198cm | 6.5-6.6 |
All Trek mountain bikes use alpha sizing instead of numeric sizing. Rather than labelling our bikes with size numbers like 17.5 and 19.5, we use sizes like M (medium) and L (large).
Why alpha sizing?
1. It’s easier to understand
'Medium' is intuitive. '17.5' is not. Alpha sizing makes it easier for you to know what Trek mountain bike will work for you. A lot of other brands also use alpha sizing, and if you ride a medium in a different brand, you’ll probably ride a medium Trek as well.
2. Frame sizes are measured differently today
Trek frame size used to be measured by the length of the seat tube. But modern mountain bike geometry is based on reach, not seat tube length. Alpha sizing is simpler and helps you find the right fit by the measurement that matters most.
Sizing conversion
The new alpha sizing corresponds with the previous numeric sizing for all models:
Alpha size
|
XS
|
S
|
M
|
ML
|
L
|
XL
|
XXL
|
Frame size
|
13.5
|
15.5
|
17.5
|
18.5
|
19.5
|
21.5
|
23
|
Rider height
|
147-155 cm 4’9”-5’1”
|
153-162 cm 5’2”-5’3.8
|
161-172 cm 5’3.4”-5’7.7”
|
170-179 cm 5’6.9”-5’10.5”
|
177-188 cm 5’9.7”-6’2”
|
186-196 cm 6’1.2”-6’5.2”
|
195-203 cm 6’4”-6’7.9”
|
Extended size range
Trek offers mountain bikes in a wide range of sizes to ensure the perfect fit for all riders. That includes an XS with increased standover height, an ML (medium-large) perfect for those in-betweeners in the middle of the sizing bell curve, and an XXL for taller riders who often struggle to find a bike that’s big enough.
Not all sizes are available on all models, but Trek’s extended size range will help any rider find a frame that fits better from the start and requires fewer changes to the cockpit.
Finding your Size
The easiest way to determine your frame size is by height, but many riders find that they are between sizes. Choosing to go up or down a size depends on your personal riding style and body proportions.
A bike with a longer reach will have a longer wheelbase. That makes it more stable, especially on high-speed descents. That’s great for riders who like to plough through rather than pop over rough stuff on the trail. If you have a relatively long torso or arms for your height, you may find that a longer reach gives you a roomier, more comfortable cockpit.
A bike with a shorter reach will have a shorter wheelbase. It’s not as stable, but it’s more nimble and easier to flick around. That’s great for riders with a more playful, active riding style who like to get off the ground and whip their wheels around. If you have a relatively short torso or arms for your height, you may find that a shorter reach makes it easier for you to hold the handlebars comfortably.
Effective top tube
Effective top tube is the horizontal distance from the centre of the head tube to the centre of the seat post. This measurement represents how a mountain bike fits while you’re sitting on the saddle. It’s important for cross country riders, who prioritise pedalling power.

Reach
Reach is the horizontal distance from the centre of the head tube to a vertical line that runs through the centre of the bottom bracket shell. This measurement represents how a mountain bike fits when you’re standing up on the pedals, like when you’re descending. Since most trail riders prioritise out-of-the-saddle riding, this tends to be the most helpful metric when comparing bike sizes from different brands.
General Size Guide
General Size Guide
Getting the right sized bike and the right fit can make a huge difference to your riding experience, ensuring you're comfortable and riding as efficiently as possible. Check out our size guide below to find the perfect frame size for you.
What you need:
Your height
Stand with your back against a wall with your shoes off and legs together. Use a pencil to make a small mark on the wall above your head then simply measure from the floor to the mark
Your inside leg length
Stand with your back against a wall with your shoes off. Position a ruler or book between your legs and then measure from the floor to the top of the ruler/book. Having someone else help will make it a little easier
Remember, all sizing information is a guide only. If you have any questions about bike sizing or differences in brands then get in touch with the Bike Shed experts. Call us on 01363 774773 or send us a message. We're here to help.
Mountain Bike Sizing (Men)
Height
|
Inside leg
|
Men's mountain bike size
|
147cm-152cm / 4'10"-5'0"
|
66cm / 26"
|
13” (X Small)
|
152cm-160cm / 5'0"-5'3"
|
69cm / 27"
|
13”, 14” (X Small)
|
160cm-170cm / 5'3"-5'7"
|
71cm / 28"
|
15”, 16" (Small)
|
170cm-175cm / 5'7"-5'9"
|
76cm / 30"
|
17", 18” (Medium)
|
175cm-180cm / 5'9"-5'11"
|
79cm / 31"
|
18”, 19" (Medium, Large)
|
180cm-188cm / 5'11"-6'2"
|
81cm / 32"
|
19", 20” (Large)
|
188cm-196cm / 6'2"-6'5"
|
86cm / 34"
|
20", 21”, 22” (Large, X Large)
|
196cm+ / 6' 5"+
|
91cm / 36"
|
23", 24” (XX Large)
|
Mountain Bike Sizing (Women)
Height
|
Inside leg
|
Women's mountain bike size
|
147cm-155cm / 4'10"-5'1"
|
66cm / 26"
|
13”, 14" (X Small)
|
155cm-160cm / 5'1"-5'3"
|
69cm / 27"
|
13”, 14” (X Small)
|
160cm-165cm / 5'3"-5'5"
|
71cm / 28"
|
15”, 16" (Small)
|
165cm-172cm / 5'5"-5'8"
|
76cm / 30"
|
17", 18” (Medium)
|
172cm+ / 5'8"+
|
79cm / 31"
|
19" (Large)
|
Road Bike Sizing (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 (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)
|
Hybrid Bike Sizing (Men)
Height
|
Inside leg
|
Men's hybrid bike size
|
147cm-152cm / 4'10"-5'0"
|
66cm / 26"
|
13”, 14" (X Small)
|
152cm-160cm / 5'0"-5'3"
|
69cm / 27"
|
14”, 15” (X Small, Small)
|
160cm-170cm / 5'3"-5'7"
|
71cm / 28"
|
15”, 16" (Small)
|
170cm-175cm / 5'7"-5'9"
|
76cm / 30"
|
17", 18” (Medium)
|
175cm-180cm / 5'9"-5'11"
|
79cm / 31"
|
19”, 20" (Large)
|
180cm-188cm / 5'11"-6'2"
|
81cm / 32"
|
20", 21” (Large, X Large)
|
188cm-196cm / 6'2"-6'5"
|
86cm / 34"
|
21”, 22” (Large, X Large)
|
196cm+ / 6' 5"+
|
91cm / 36"
|
23", 24” (XX Large)
|
Hybrid Bike Sizing (Women)
Height
|
Inside leg
|
Women's hybrid bike size
|
147cm-155cm / 4'10"-5'1"
|
66cm / 26"
|
13”, 14" (X Small)
|
155cm-160cm / 5'1"-5'3"
|
69cm / 27"
|
14”, 15” (X Small, Small)
|
160cm-165cm / 5'3"-5'5"
|
71cm / 28"
|
15”, 16" (Small)
|
165cm-172cm / 5'5"-5'8"
|
76cm / 30"
|
17", 18” (Medium)
|
172cm+ / 5'8"+
|
79cm / 31"
|
19" (Large)
|