Trek publishes a chart with the recommended rider height and inseam for each size on every bike’s page, and groups them by family: all the new road bikes share one chart, all the mountain bikes another. These are the charts for its best-selling models (Trek spec pages checked in October 2026), cross-checked against the charts two Trek dealers publish. The feet-and-inches figures match the ones Trek shows on its US site, which rounds to the nearest inch; the centimeters are Trek’s own. Inseam is the distance from the floor to your crotch, barefoot.
Trek road bike sizes: Domane and Madone
The Domane SL and SLR (Gen 5) and the Madone (Gen 8) use the same chart. The equivalent frame number is in parentheses.
| Size | Rider height | Inseam | Domane SL 5 stack / reach |
|---|---|---|---|
| XS (47) | 4 ft 8 in–5 ft 2 in (143-158 cm) | 26-29 in (67-74 cm) | 524 / 368 mm |
| S (50) | 5 ft 2 in–5 ft 4 in (158-162 cm) | 29-30 in (74-76 cm) | 555 / 371 mm |
| M (52-54) | 5 ft 4 in–5 ft 8 in (162-173 cm) | 30-32 in (76-81 cm) | 575 / 374 mm |
| ML (56) | 5 ft 8 in–5 ft 10 in (173-179 cm) | 32-33 in (81-84 cm) | 596 / 377 mm |
| L (58) | 5 ft 10 in–6 ft 2 in (179-188 cm) | 33-35 in (84-88 cm) | 618 / 380 mm |
| XL (60-62) | 6 ft 2 in–6 ft 6 in (188-199 cm) | 35-39 in (88-100 cm) | 648 / 384 mm |
Trek numbered road sizes: Domane AL
| Size | Rider height | Inseam |
|---|---|---|
| 44 | 4 ft 11 in–5 ft (150-153 cm) | 28-29 in (71-73 cm) |
| 49 | 5 ft 1 in–5 ft 4 in (156-163 cm) | 29-30 in (74-77 cm) |
| 52 | 5 ft 4 in–5 ft 6 in (163-168 cm) | 30-31 in (76-79 cm) |
| 54 | 5 ft 6 in–5 ft 9 in (168-174 cm) | 31-32 in (78-82 cm) |
| 56 | 5 ft 9 in–5 ft 11 in (174-180 cm) | 32-33 in (81-85 cm) |
| 58 | 5 ft 11 in–6 ft 1 in (180-185 cm) | 33-34 in (84-87 cm) |
| 61 | 6 ft 1 in–6 ft 3 in (185-191 cm) | 34-35 in (86-90 cm) |
Trek gravel bike sizes: Checkpoint
Checkpoint ALR and SL, 3rd generation. Note that the ranges don’t match the Domane’s: the gravel ML goes up to 6 ft 2 in (188 cm).
| Size | Rider height | Inseam | Checkpoint ALR stack / reach |
|---|---|---|---|
| XS | 4 ft 8 in–5 ft 2 in (143-158 cm) | 26-29 in (67-74 cm) | 545 / 380 mm |
| S (49) | 5 ft 2 in–5 ft 5 in (158-164 cm) | 29-30 in (74-77 cm) | 566 / 385 mm |
| M (52-54) | 5 ft 5 in–5 ft 10 in (164-177 cm) | 30-33 in (77-83 cm) | 589 / 391 mm |
| ML (56) | 5 ft 10 in–6 ft 2 in (177-188 cm) | 33-35 in (83-88 cm) | 611 / 397 mm |
| L (58) | 6 ft 2 in–6 ft 4 in (188-194 cm) | 35-36 in (88-91 cm) | 630 / 402 mm |
| XL (61) | 6 ft 4 in–6 ft 8 in (194-203 cm) | 36-37 in (91-95 cm) | 650 / 408 mm |
Trek mountain bike sizes: Marlin, Procaliber, Fuel EX and Top Fuel
All four share ranges, but not every model comes in every size: the Procaliber and Top Fuel run S to XL, the Fuel EX XS to 2XL, and the Marlin (entry-level hardtail) 2XS to 2XL.
| Size | Rider height | Inseam | Fuel EX 8 reach |
|---|---|---|---|
| 2XS | 4 ft 5 in–4 ft 9 in (135-145 cm) | 25-27 in (64-68 cm) | — |
| XS | 4 ft 9 in–5 ft 1 in (145-155 cm) | 27-29 in (69-73 cm) | 400 mm |
| S | 5 ft 1 in–5 ft 5 in (155-165 cm) | 29-31 in (74-78 cm) | 425 mm |
| M | 5 ft 5 in–5 ft 10 in (165-177 cm) | 31-33 in (79-83 cm) | 450 mm |
| ML | 5 ft 8 in–5 ft 11 in (173-180 cm) | 32-34 in (81-86 cm) | 470 mm |
| L | 5 ft 10 in–6 ft 2 in (177-188 cm) | 33-35 in (84-89 cm) | 485 mm |
| XL | 6 ft 2 in–6 ft 5 in (188-195 cm) | 35-36 in (89-91 cm) | 515 mm |
| 2XL | 6 ft 5 in–6 ft 8 in (195-203 cm) | 36-38 in (91-97 cm) | — |
City: FX Sport
| Size | Rider height | Inseam |
|---|---|---|
| XS | 4 ft 10 in–5 ft 1 in (147-155 cm) | 27-29 in (69-73 cm) |
| S | 5 ft 1 in–5 ft 5 in (155-165 cm) | 28-31 in (72-78 cm) |
| M | 5 ft 5 in–5 ft 9 in (165-175 cm) | 30-33 in (77-83 cm) |
| L | 5 ft 9 in–6 ft 1 in (175-186 cm) | 32-35 in (82-88 cm) |
| XL | 6 ft 1 in–6 ft 6 in (186-197 cm) | 34-37 in (87-93 cm) |
If you’re between two sizes
Trek is one of the few brands that lists inseam, so use it: if your height says ML but your inseam says M, you have a long torso, and either the ML with a short stem or the M with a long stem will suit you better; try before you buy.
- On mountain bikes, the ML is there for riders on the edge: for a nimble bike on tight, twisty singletrack, go smaller; if you descend fast or ride long days, go larger (more reach and a longer wheelbase).
- On road bikes, compare the reach: on the Domane it only grows 3 mm per size, but the stack rises about 20 mm. If what bothers you is riding low, the larger size raises the bars without pushing them away; if the bars feel too far, go smaller.
With your inseam measured (how to find your bike size explains how), the bike size calculator gives you a starting point and the bike geometry comparison lets you put the Trek next to your current bike. To see what size you’d ride in other brands, check the size chart by brand.
Frequently asked questions
What size Trek Domane do I need if I'm 5'9"?
An ML (equivalent to a 56 cm frame), which Trek lists for 5 ft 8 in to 5 ft 10 in (173-179 cm) and a 32-33 in (81-84 cm) inseam. If your inseam is over 33 in (84 cm), look at the L too.
What is a Trek ML size?
The in-between size from medium to large. On road bikes it's equivalent to a 56; on mountain bikes it covers 5 ft 8 in to 5 ft 11 in (173-180 cm) and overlaps the M and L so riders on the edge can choose by reach.
Why do some Domanes have letter sizes and others numbers?
Trek has moved its road bikes from numbers to letters. The 5th-generation Domane SL and SLR and the 8th-generation Madone use XS to XL; the aluminum Domane AL still uses numbers from 44 to 61.
Which matters more for Trek sizing, height or inseam?
Trek lists both. If they point to different sizes, your inseam sets your saddle height and your overall height hints at your torso length: with long legs and a short torso, the smaller size usually works better.
Sources
- Trek: Domane SL 5 Gen 5, size chart and geometry
- Trek US: Domane SL 5 Gen 5 sizing data (product API)
- Trek US: Checkpoint ALR 4 Gen 3 sizing data
- Trek US: Fuel EX 8 Gen 6 sizing data
- Trek: sizing and fit guide
- Rêve de Vélo (retailer): Trek Domane SL 5 Gen 5 size chart
- Ridley's (retailer): Trek Domane size chart in numbered sizes