Sizing a Trek road bike
Trek's road range recently simplified. The lightweight Emonda has been folded into the latest Madone, so the Madone SLR is now both the aero and the climbing bike in one race platform, and it has switched to letter sizes. The Domane SLR remains the endurance bike on the familiar numeric scale, and it sits much taller and shorter for comfort. Pick the model for its fit character, then size by height and reach.
Browse the range: all Trek bikes at Bikeroom.
Please note. These sizes are a starting point, not a guarantee. The Madone now uses letters (XS to XL) while the Domane uses cm numbers (47 to 62), so compare reach and stack rather than the label. A fit check settles any doubt.
Quick size finder
Find your height, cross check your inside leg, and read across. The race Madone uses letters; the endurance Domane uses cm sizes.
| Rider height | Leg length (inseam) | Madone SLR (race) | Domane SLR (endurance) |
|---|---|---|---|
| 152 to 158 cm | 71 to 75 cm | XS | 47 |
| 158 to 163 cm | 74 to 78 cm | S | 50 |
| 162 to 169 cm | 77 to 82 cm | M | 52 |
| 167 to 175 cm | 80 to 85 cm | M or M/L | 54 |
| 173 to 179 cm | 84 to 88 cm | M/L | 56 |
| 179 to 186 cm | 87 to 91 cm | L | 58 |
| 184 to 191 cm | 90 to 95 cm | L or XL | 60 |
| 189 to 196 cm | 94 to 99 cm | XL | 62 |
At the same height the Domane sits more upright, taller in stack and shorter in reach, than the Madone. If you want a race position from the Domane, consider the smaller size.
How to measure yourself
Height. Stand barefoot against a wall, heels together, and measure to the top of your head.
Leg length (inseam). Barefoot, feet about 15 cm apart, press a book up to the wall like a saddle and measure floor to spine.
Then use reach. Because the two bikes use different scales and fits, match the reach below to a bike you like to pick the right one.
Madone SLR (race and lightweight)
The Madone SLR is the current all rounder, combining the old aero Madone and the lightweight Emonda in one race platform, with a low, long, fast position. It uses six letter sizes rather than the old cm numbers. Available in 6 sizes: XS to XL.
| Frame size | XS | S | M | M/L | L | XL |
|---|---|---|---|---|---|---|
| Stack (mm) | 507 | 530 | 546 | 562 | 582 | 610 |
| Reach (mm) | 370 | 378 | 384 | 389 | 394 | 402 |
| Rider height | 152 to 158 | 158 to 163 | 162 to 173 | 173 to 179 | 179 to 188 | 188 to 199 |
As a rough guide to the old numbers, XS is about a 50, S a 52, M a 54, M/L a 56, L a 58 and XL a 60 to 62. Between the M and M/L, pick on front end height first and fine tune reach with the stem.
Domane SLR (endurance)
The Domane SLR is the endurance bike, with the tallest stack and shortest reach of the range and rear IsoSpeed for comfort. It sits you upright over a long wheelbase for all day and rough road riding. Available in 8 sizes: 47 to 62.
| Frame size | 47 | 50 | 52 | 54 | 56 | 58 | 60 | 62 |
|---|---|---|---|---|---|---|---|---|
| Stack (mm) | 527 | 546 | 561 | 575 | 591 | 611 | 632 | 656 |
| Reach (mm) | 364 | 368 | 371 | 374 | 377 | 380 | 383 | 386 |
| Rider height | 152 to 159 | 157 to 164 | 162 to 169 | 167 to 175 | 173 to 181 | 179 to 186 | 184 to 191 | 189 to 195 |
Rear IsoSpeed smooths rough roads and is widely praised. Because reach is short and stack tall, riders between sizes often size down for a slightly sportier reach.
What Trek riders find
The Madone Gen 8 combines the old aero and lightweight bikes, so if you rode an Emonda or Madone before, expect the same race feel on the new letter sizes; between the M and M/L, pick on stack first and adjust reach with the stem. Note the current bar and stem sit a few millimetres higher than the previous generation. The Domane is loved for its IsoSpeed comfort and tends to fit large and upright for a given height, so retailers warn it can lean a size bigger than expected; many riders size down for a sportier reach or choose by inseam and comfort, and test riding two sizes is worth it. In general Trek riders favour the smaller frame when truly on the border, since a short bike is easier to lengthen than a long one is to shorten.
Between two sizes?
On the Madone, choose by front end height then set reach with the stem. On the Domane, lean smaller for a racier reach or stay larger for maximum upright comfort. Send us your height, inside leg and current bike's reach and we will confirm.
Shop Trek road
- All Trek bikes including the Madone SLR and Domane SLR
Race or endurance? Ask our concierge
The Madone and Domane use different size scales and fit quite differently, so it is worth a quick check. Share your height, inside leg and riding style and our concierge team will recommend the model and size. Talk to our concierge.
These sizes are guidance, not a fitting guarantee. Stack and reach are official Trek data; the Madone now uses letter sizes and the Emonda has merged into it, while the Domane uses cm numbers. Rider height ranges follow Trek's charts, so confirm against the specific bike you are buying.
