Road Mountain / MTB Gravel City & hybrid BMX Dirt jump Triathlon / TT Kids Women Men

BIKZER · Sizing guides

Men’s bike size guide and calculator

A men’s category does not define a frame dimension. Start with height and inseam, choose the discipline and check the geometry of the specific bike.

Editorial responsibility: Gonzalo Caballero González · Reviewed: 2026-09-18

BIKZER / Sizing guides

Find your reference bike size

Your sizing reference

Enter your measurements to check the chart.

Read our method and limitations →

01 / How to measure

Height

Stand barefoot against a wall and look straight ahead.
Place a level book on your head and mark its lower edge.
Measure from the floor to the mark. Repeat to check consistency.

02 / How to measure

Inseam

Stand barefoot against a wall with your feet slightly apart.
Hold a level book between your legs with firm, comfortable pressure.
Measure from the floor to the top edge. Do not use your trouser inseam.

Proportions explain different fits

Two riders of the same height can have different leg, torso and arm lengths. Inseam helps cross-check a chart but cannot determine handlebar reach by itself. If the measurements do not match one row, measure again and inspect the geometry rather than ignoring the measurement that disagrees.

Check contact points individually

Saddle shape, handlebar width and brake reach deserve their own checks. Do not infer them from gender or clothing size. Adjust components to your proportions within manufacturer limits; persistent discomfort calls for an individual assessment.

Compare new and used bikes carefully

Ask for the model, year, frame size and geometry chart. A photo or the seller’s height is not enough. Check that the seatpost and cockpit still have adjustment room, and try the bike if possible. With a used bike, assess mechanical condition and fit separately: both matter.

Frequently asked questions

Can a man use a bike marketed to women?

The label does not decide fit. Compare geometry, available sizes, components and intended use.

Can I use my clothing size?

It is not a consistent bike measurement. Measure height and inseam and consult the bike brand’s chart.

Is this calculation different from the main tool?

It uses the same discipline-specific measurements. This guide adds comparison advice, not a gender coefficient.

Sources and model checks

Reference size chart

Road

Bikzer reference ranges are not universal size conversions between brands. Overlapping ranges provide several options. Charts always show both units.

Scroll the table sideways to see every column.

Reference size chart · Road
Frame (cm)	Rider height	Reference inseam
47-49	150–158 cm4′ 11.06″–5′ 2.2″	70–73 cm27.56–28.74 in
49-51	158–163 cm5′ 2.2″–5′ 4.17″	73–76 cm28.74–29.92 in
51-53	163–168 cm5′ 4.17″–5′ 6.14″	76–79 cm29.92–31.1 in
53-55	168–173 cm5′ 6.14″–5′ 8.11″	79–82 cm31.1–32.28 in
55-56	173–178 cm5′ 8.11″–5′ 10.08″	82–84 cm32.28–33.07 in
56-58	178–183 cm5′ 10.08″–6′ 0.05″	84–87 cm33.07–34.25 in
58-60	183–188 cm6′ 0.05″–6′ 2.02″	87–90 cm34.25–35.43 in
60-62	188–193 cm6′ 2.02″–6′ 3.98″	90–93 cm35.43–36.61 in
62+	193–210 cm6′ 3.98″–6′ 10.68″	93–110 cm36.61–43.31 in

Mountain / MTB

Bikzer reference ranges are not universal size conversions between brands. Overlapping ranges provide several options. Charts always show both units.

Scroll the table sideways to see every column.

Reference size chart · Mountain / MTB
Frame	Rider height	Reference inseam
XS	145–155 cm4′ 9.09″–5′ 1.02″	69–73 cm27.17–28.74 in
S	155–165 cm5′ 1.02″–5′ 4.96″	74–78 cm29.13–30.71 in
M	165–176 cm5′ 4.96″–5′ 9.29″	79–83 cm31.1–32.68 in
M/L	173–180 cm5′ 8.11″–5′ 10.87″	81–86 cm31.89–33.86 in
L	177–188 cm5′ 9.69″–6′ 2.02″	84–89 cm33.07–35.04 in
XL	188–195 cm6′ 2.02″–6′ 4.77″	89–91 cm35.04–35.83 in
2XL	195–203 cm6′ 4.77″–6′ 7.92″	91–97 cm35.83–38.19 in

BMX

Bikzer reference ranges are not universal size conversions between brands. Overlapping ranges provide several options. Charts always show both units.

Scroll the table sideways to see every column.

Reference size chart · BMX
Top tube (TT) / Wheel (in)	Rider height
TT 18"-20" / Ø 20"	135–155 cm4′ 5.15″–5′ 1.02″
TT 20"-20.25" / Ø 20"	147–162 cm4′ 9.87″–5′ 3.78″
TT 20"-20.5" / Ø 20"	157–173 cm5′ 1.81″–5′ 8.11″
TT 20.25"-21" / Ø 20"	167–183 cm5′ 5.75″–6′ 0.05″
TT 20.75"+ / Ø 20"	180–220 cm5′ 10.87″–7′ 2.61″

City & hybrid

Bikzer reference ranges are not universal size conversions between brands. Overlapping ranges provide several options. Charts always show both units.

Scroll the table sideways to see every column.

Reference size chart · City & hybrid
Frame	Rider height
XS	148–158 cm4′ 10.27″–5′ 2.2″
S	158–168 cm5′ 2.2″–5′ 6.14″
M	168–178 cm5′ 6.14″–5′ 10.08″
L	178–185 cm5′ 10.08″–6′ 0.83″
XL	185–193 cm6′ 0.83″–6′ 3.98″
XXL	193–198 cm6′ 3.98″–6′ 5.95″

Gravel

Bikzer reference ranges are not universal size conversions between brands. Overlapping ranges provide several options. Charts always show both units.

Scroll the table sideways to see every column.

Reference size chart · Gravel
Frame (cm)	Rider height	Reference inseam
43/45	144.7–152.4 cm4′ 8.97″–5′ 0″	67.3–71.2 cm26.5–28.03 in
47/48	152.4–167.6 cm5′ 0″–5′ 5.98″	71.2–75 cm28.03–29.53 in
51	167.6–172.7 cm5′ 5.98″–5′ 7.99″	75–77 cm29.53–30.31 in
54	172.7–177.8 cm5′ 7.99″–5′ 10″	76–82 cm29.92–32.28 in
56	177.8–182.8 cm5′ 10″–5′ 11.97″	81–85 cm31.89–33.46 in
58	182.8–187.9 cm5′ 11.97″–6′ 1.98″	84–87.1 cm33.07–34.29 in
61	187.9–195.5 cm6′ 1.98″–6′ 4.97″	87.1–91.1 cm34.29–35.87 in

Dirt jump

Bikzer reference ranges are not universal size conversions between brands. Overlapping ranges provide several options. Charts always show both units.

Scroll the table sideways to see every column.

Reference size chart · Dirt jump
Wheel and geometry	Rider height
24" · TT ~20"-22"	135–155 cm4′ 5.15″–5′ 1.02″
24" · TT ~20"-22.7"	150–175 cm4′ 11.06″–5′ 8.9″
26" · Reach ~410-415 mm; standover ~710-715 mm	155–170 cm5′ 1.02″–5′ 6.93″
26" · Reach ~425-435 mm; standover ~710-715 mm	170–210 cm5′ 6.93″–6′ 10.68″
26" · TT ~21"-24.5"	160–185 cm5′ 2.99″–6′ 0.83″

Triathlon / TT

Bikzer reference ranges are not universal size conversions between brands. Overlapping ranges provide several options. Charts always show both units.

Scroll the table sideways to see every column.

Reference size chart · Triathlon / TT
Frame (cm)	Rider height	Reference inseam
47-49	150–160 cm4′ 11.06″–5′ 2.99″	65–70 cm25.59–27.56 in
50-52	160–170 cm5′ 2.99″–5′ 6.93″	70–75 cm27.56–29.53 in
53-54	170–175 cm5′ 6.93″–5′ 8.9″	76–80 cm29.92–31.5 in
55-56	176–182 cm5′ 9.29″–5′ 11.65″	80–85 cm31.5–33.46 in
57-59	183–190 cm6′ 0.05″–6′ 2.8″	85–90 cm33.46–35.43 in
60-62	190–205 cm6′ 2.8″–6′ 8.71″	90–110 cm35.43–43.31 in

Kids

Children’s reference based on Trek’s guide, converted to centimetres. Fit also depends on the model, brake reach and minimum saddle height. The 26″ range is capped at 158 cm in this tool.

Scroll the table sideways to see every column.

Reference size chart · Kids
Wheel	Rider height	Reference inseam
12″	91.44–99.06 cm3′ 0″–3′ 3″	38.1–45.72 cm15–18 in
16″	104.14–121.92 cm3′ 5″–4′ 0″	40.64–55.88 cm16–22 in
20″	114.3–137.16 cm3′ 9″–4′ 6″	48.26–63.5 cm19–25 in
24″	124.46–149.86 cm4′ 1″–4′ 11″	58.42–71.12 cm23–28 in
26″	142.24–158 cm4′ 8″–5′ 2.2″	≥ 63.5 cm≥ 25 in