Trek Fuel EX Size Chart
Fuel EX runs XS to XXL in seven sizes, and Trek publishes rider height and inseam for each one. The numbers below are the Low geometry position, which is the setting Trek ships.
- Frame sizes
- XS–XXL · 7 sizes
- Rider height
- 4'9"–6'8"
- Height (cm)
- 145–203 cm
- Stack / reach · M
- 617 / 450 mm
Fuel EX 8 Gen 6 size finder
Which Fuel EX 8 Gen 6 size covers your height?
Height gives you one size, or two when the published height ranges overlap. Stack, reach, and standover settle the overlap.
Enter your height and the Fuel EX 8 Gen 6 size that covers it is marked in the tables below.
How to measureHeight gives the starting size. Standover and reach confirm it.
Height ranges
Where each size starts and ends
Height ranges for every Fuel EX 8 Gen 6 size, 141 to 207 cm overall. XS: 145 to 155 cm. S: 155 to 165 cm. M: 165 to 177 cm. ML: 173 to 180 cm. L: 177 to 188 cm. XL: 188 to 195 cm. XXL: 195 to 203 cm.
- XS145–155 cm
- S155–165 cm
- M165–177 cm
- ML173–180 cm
- L177–188 cm
- XL188–195 cm
- XXL195–203 cm
Size chart
Fuel EX 8 Gen 6 size by height
Rider height and inseam are Trek's published Fuel EX table. The XS frame is 27.5-inch, S offers both wheel sizes, and M and up are 29-inch.
XS
4'9"–5'1"
145–155 cm
Smallest Fuel EX frame and the only 27.5-inch one, with the lowest standover at 717 mm.
S
5'1"–5'5"
155–165 cm
Stack adds 38 mm over XS, the largest stack step in the ladder. Trek builds S in 27.5-inch and 29-inch.
M
5'5"–5'10"
165–177 cm
Stack and reach above are for this size. Stack matches ML at 617 mm.
ML
5'8"–5'11"
173–180 cm
Same stack as M, 20 mm more reach, and 5 mm more standover.
L
5'10"–6'2"
177–188 cm
Reach adds 15 mm over ML, the smallest reach step in the ladder.
XL
6'2"–6'5"
188–195 cm
Reach adds 30 mm over L and another 30 mm to XXL, the largest reach steps in the ladder.
XXL
6'5"–6'8"
195–203 cm
Tallest Fuel EX frame, with the highest standover in the table at 774 mm.
Start with height. If two sizes overlap, use cycling inseam to choose.How to measure
Geometry
Fuel EX 8 Gen 6 geometry by size
Stack, reach, and standover for every Fuel EX 8 Gen 6 size, read from the Low position of Trek's geometry table. Trek also publishes a High position, which changes stack by 2 to 5 mm on the same frame.
XS
4'9"–5'1"
- Stack
- 574 mm
- Reach
- 400 mm
- Standover
- 717 mm
S
5'1"–5'5"
- Stack
- 612 mm
- Reach
- 425 mm
- Standover
- 737 mm
M
5'5"–5'10"
- Stack
- 617 mm
- Reach
- 450 mm
- Standover
- 737 mm
ML
5'8"–5'11"
- Stack
- 617 mm
- Reach
- 470 mm
- Standover
- 742 mm
L
5'10"–6'2"
- Stack
- 621 mm
- Reach
- 485 mm
- Standover
- 748 mm
XL
6'2"–6'5"
- Stack
- 635 mm
- Reach
- 515 mm
- Standover
- 767 mm
XXL
6'5"–6'8"
- Stack
- 648 mm
- Reach
- 545 mm
- Standover
- 774 mm
XS4'9"–5'1"
Stack574 mmReach400 mmS5'1"–5'5"
Stack612 mmReach425 mmM5'5"–5'10"
Stack617 mmReach450 mmML5'8"–5'11"
Stack617 mmReach470 mmL5'10"–6'2"
Stack621 mmReach485 mmXL6'2"–6'5"
Stack635 mmReach515 mmXXL6'5"–6'8"
Stack648 mmReach545 mm
How neighboring sizes compare
If two sizes both fit, compare reach and standover rather than assuming the larger size is more comfortable.
How to measure a bike frame- Size stepStackReachStandover
- XS → S+38 mm+25 mm+20 mm
- S → M+5 mm+25 mm0 mm
- M → ML0 mm+20 mm+5 mm
- ML → L+4 mm+15 mm+6 mm
- L → XL+14 mm+30 mm+19 mm
- XL → XXL+13 mm+30 mm+7 mm
Bike size calculator
Find your Trek Fuel EX 8 Gen 6 size
Enter your height and inseam for a Trek mountain bike, then compare the result with this Fuel EX 8 Gen 6 chart.
Sizing notes
Why height alone is not enough
Riders with the same height can need different sizes because inseam, torso length, flexibility, and preferred handling differ.
3 checks
Reach grows 145 mm from XS to XXL while stack climbs 74 mm, so the trail frame gets about twice as long as it gets taller.
Standover climbs 57 mm across the ladder. The largest step is XS to S at 20 mm, and M matches ML at 737 mm.
Four of the seven sizes share a reach step of 15 to 25 mm, so reach is the number that separates them. Confirm it on the frame you are buying.
Sources
Confirm the exact bike after you have a starting size
Every number on this page comes from the sources below. Check the exact model year there before you buy.
Data reviewed:
Compare
Compare before buying
A size label does not mean the same thing across brands. Compare published geometry before you choose.
Related guides
More Trek and mountain sizing
Once you have a starting size, compare this frame against the Trek chart and the mountain guide.
Trek bike size chart
Compare Fuel EX 8 Gen 6 against broader Trek size guidance.
Mountain bike size chart
Check mountain sizing by height and inseam before choosing a frame.
Questions
Fuel EX 8 Gen 6 size chart FAQ
Short answers for Trek Fuel EX 8 Gen 6 sizing.
What size Trek Fuel EX should I ride?
Start with Trek's height range: XS for 145–155 cm, S for 155–165 cm, M for 165–177 cm, ML for 173–180 cm, L for 177–188 cm, XL for 188–195 cm, and XXL for 195–203 cm. Then confirm standover for the size you land on.
What size Fuel EX fits a 172 cm rider?
172 cm sits inside Trek's M range of 165–177 cm. It carries 617 mm of stack, 450 mm of reach, and 737 mm of standover. ML starts at 173 cm, so a rider at 172 cm is at the edge of both.
Does the Fuel EX use the same size numbers as the Marlin?
The labels match but the frames do not. Fuel EX M covers 165–177 cm and Marlin M covers 165–177 cm, yet the two carry different stack and reach, so check the numbers for the bike you are buying.
How tall is a Trek Fuel EX ML for?
Trek publishes Fuel EX ML for 173–180 cm, which is 5'8"–5'11". It carries 617 mm of stack, 470 mm of reach, and 742 mm of standover.
Which wheel size does each Fuel EX size use?
XS is 27.5-inch, S is built in both wheel sizes, and M through XXL are 29-inch. Trek lists the wheel size beside each size in its geometry table.