★ SPORTS · BIKE FRAME SIZE CHART · ROAD, MOUNTAIN & HYBRID
At 70 inches tall your frame is a road 57–59 cm, a mountain 17–18 in, or a hybrid 18–19 in — inseam about 31.50 in (80.01 cm). Put in your height and the calculator finds your frame size band for road, mountain and hybrid bikes, with the midpoints and an inseam estimate.
Frame sizes by rider height, for road, mountain and hybrid bikes — published manufacturer size ranges, looked up by height band, with the midpoint of each range and an inseam estimate. Put in your height and the calculator finds your band.
The seven height bands, with the road, mountain and hybrid frame ranges, the midpoint of each range, and the inseam estimate at the middle of the band. The table uses published manufacturer size ranges; the calculator is a band lookup with midpoints.
| Height (in) | Road frame (cm) | Mountain frame (in) | Hybrid frame (in) | Midpoints (road / MTB / hybrid) | Inseam at mid-height (in / cm) |
|---|---|---|---|---|---|
| 58–61 | 47–48 | 13–14 | 13–15 | 47.5 / 13.5 / 14 | 26.78 / 68.02 |
| 61–64 | 49–50 | 14–15 | 15–16 | 49.5 / 14.5 / 15.5 | 28.13 / 71.45 |
| 64–67 | 51–53 | 15–16 | 16–17 | 52 / 15.5 / 16.5 | 29.48 / 74.88 |
| 67–70 | 54–56 | 16–17 | 17–18 | 55 / 16.5 / 17.5 | 30.83 / 78.31 |
| 70–73 | 57–59 | 17–18 | 18–19 | 58 / 17.5 / 18.5 | 32.18 / 81.74 |
| 73–76 | 60–62 | 18–19 | 19–20 | 61 / 18.5 / 19.5 | 33.53 / 85.17 |
| 76–79 | 63–65 | 19–21 | 20–22 | 64 / 20 / 21 | 34.88 / 88.60 |
On the defaults — 70 inches tall — the band is 70–73 in: a road frame of 57–59 cm (midpoint 58), a mountain frame of 17–18 in (midpoint 17.5), and a hybrid frame of 18–19 in (midpoint 18.5), with an inseam estimate of 31.50 in (80.01 cm). The bands are half-open: a height of exactly 70 inches is in the 70–73 band, not the 67–70 band, and 69.5 inches is in the 67–70 band. The inseam estimate is height × 0.45 in inches, times 2.54 for centimetres — a rough guide, not a measurement: measure your real inseam before ordering a frame. Road frames are measured in centimetres (seat tube length), mountain and hybrid frames in inches.
58 in: road 47–48 cm (mid 47.5), MTB 13–14 in (mid 13.5), hybrid 13–15 in (mid 14); inseam 26.10 in (66.29 cm). The smallest band in the table.
61 in: road 49–50 cm (mid 49.5), MTB 14–15 in (mid 14.5), hybrid 15–16 in (mid 15.5); inseam 27.45 in (69.72 cm). The first step up — 61 inches is the bottom of the second band.
64 in: road 51–53 cm (mid 52), MTB 15–16 in (mid 15.5), hybrid 16–17 in (mid 16.5); inseam 28.80 in (73.15 cm).
67 in: road 54–56 cm (mid 55), MTB 16–17 in (mid 16.5), hybrid 17–18 in (mid 17.5); inseam 30.15 in (76.58 cm).
73 in: road 60–62 cm (mid 61), MTB 18–19 in (mid 18.5), hybrid 19–20 in (mid 19.5); inseam 32.85 in (83.44 cm). The bottom of the second-largest band.
76 in: road 63–65 cm (mid 64), MTB 19–21 in (mid 20), hybrid 20–22 in (mid 21); inseam 34.20 in (86.87 cm). The largest band in the table.
Smallest height for the 49–50 cm road band: 61 in — at 61 in the road frame is 49–50 cm; at 60.5 in it is 47–48 cm. The star is INCHES.
Smallest height for the 51–53 cm road band: 64 in — at 64 in the road frame is 51–53 cm; at 63.5 in it is 49–50 cm. The star is INCHES.
Smallest height for the 54–56 cm road band: 67 in — at 67 in the road frame is 54–56 cm; at 66.5 in it is 51–53 cm. The star is INCHES.
Smallest height for the 57–59 cm road band: 70 in — at 70 in the road frame is 57–59 cm; at 69.5 in it is 54–56 cm. The star is INCHES.
Smallest height for the 60–62 cm road band: 73 in — at 73 in the road frame is 60–62 cm; at 72.5 in it is 57–59 cm. The star is INCHES.
Smallest height for the 63–65 cm road band: 76 in — at 76 in the road frame is 63–65 cm; at 75.5 in it is 60–62 cm. The star is INCHES.
The table uses published manufacturer size ranges; the calculator is a band lookup with midpoints — it does not measure your body, and two riders of the same height can need different frames because of arm length, torso length and riding style. The inseam estimate is height × 0.45, a rough guide — measure your real inseam before ordering. The bands are half-open [lo, hi): a height on a boundary belongs to the band above it. 57.5 in has no standard size (below the table) and 79 in has no standard size (above the table) — both are model-level outcomes, not errors. 78.9 in is still in the largest band (76–79): road 63–65 cm, MTB 19–21 in, hybrid 20–22 in, inseam 35.51 in (90.20 cm). 58 in is the bottom of the first band, and 0 in has no standard size. The table cells are derived from the stated rules — midpoints are the average of each range, inseam = height × 0.45 in, cm = in × 2.54 — never hand-typed.
| Output | Formula | What it means |
|---|---|---|
| Height band | the [lo, hi) band containing the height | 70–73 in. |
| Road frame | published manufacturer range for the band | 57–59 cm. |
| Mountain frame | published manufacturer range for the band | 17–18 in. |
| Hybrid frame | published manufacturer range for the band | 18–19 in. |
| Road midpoint | (57 + 59) ÷ 2 | 58 cm. |
| Mountain midpoint | (17 + 18) ÷ 2 | 17.5 in. |
| Hybrid midpoint | (18 + 19) ÷ 2 | 18.5 in. |
| Inseam estimate (in) | height × 0.45 | 31.50 in. |
| Inseam estimate (cm) | inseam in × 2.54 | 80.01 cm. |
| Smallest height for the 49–50 cm band | 61 in (60.5 in gives 47–48 cm) | 61 in → 61 in. |
| Smallest height for the 51–53 cm band | 64 in (63.5 in gives 49–50 cm) | 64 in → 64 in. |
| Smallest height for the 54–56 cm band | 67 in (66.5 in gives 51–53 cm) | 67 in → 67 in. |
| Smallest height for the 57–59 cm band | 70 in (69.5 in gives 54–56 cm) | 70 in → 70 in. |
| Smallest height for the 60–62 cm band | 73 in (72.5 in gives 57–59 cm) | 73 in → 73 in. |
| Smallest height for the 63–65 cm band | 76 in (75.5 in gives 60–62 cm) | 76 in → 76 in. |
| Height 58 in | same model | Road 47–48 cm (mid 47.5), MTB 13–14 in (mid 13.5), Hybrid 13–15 in (mid 14); inseam 26.10 in (66.29 cm). |
| Height 61 in | same model | Road 49–50 cm (mid 49.5), MTB 14–15 in (mid 14.5), Hybrid 15–16 in (mid 15.5); inseam 27.45 in (69.72 cm). |
| Height 64 in | same model | Road 51–53 cm (mid 52), MTB 15–16 in (mid 15.5), Hybrid 16–17 in (mid 16.5); inseam 28.80 in (73.15 cm). |
| Height 67 in | same model | Road 54–56 cm (mid 55), MTB 16–17 in (mid 16.5), Hybrid 17–18 in (mid 17.5); inseam 30.15 in (76.58 cm). |
| Height 73 in | same model | Road 60–62 cm (mid 61), MTB 18–19 in (mid 18.5), Hybrid 19–20 in (mid 19.5); inseam 32.85 in (83.44 cm). |
| Height 76 in | same model | Road 63–65 cm (mid 64), MTB 19–21 in (mid 20), Hybrid 20–22 in (mid 21); inseam 34.20 in (86.87 cm). |
The table is first-principles: the bands are the published manufacturer size ranges, the midpoints are the average of each range, and the inseam estimate is height times 0.45 in inches, times 2.54 for centimetres — every cell is derived from those rules to 2dp half-up, never hand-typed. What the chart cannot do is fit YOUR body: two riders of the same height can need different frames because of arm length, torso length, flexibility and riding style, and manufacturers measure frames differently — road frames by seat tube length in centimetres, mountain and hybrid frames in inches, and some brands use S/M/L instead. The inseam estimate is a rough guide, not a measurement. Use the chart to narrow the choice to one band, then test-ride before you buy.
Bright Side Kit. "Bike Frame Size Chart: Road, Mountain & Hybrid 2026" https://brightoolbox.com/bike-frame-size-chart/ Accessed October 26, 2026.Road 57–59 cm, mountain 17–18 in, hybrid 18–19 in. At 70 inches you are in the 70–73 inch band: road midpoint 58 cm, mountain midpoint 17.5 in, hybrid midpoint 18.5 in, inseam estimate 31.50 in (80.01 cm).
57–59 cm. 5 ft 10 in is 70 inches, which is the bottom of the 70–73 inch band — road 57–59 cm, midpoint 58 cm.
Road frames are measured in centimetres, mountain and hybrid frames in inches. The usual measure is the seat tube length, but brands measure differently — use your height to find the band, then test-ride.
They use different units and different geometry. At 70 inches: road 57–59 cm, mountain 17–18 in, hybrid 18–19 in. A mountain frame is shorter than a hybrid frame for the same rider, because mountain bikes are built for an upright, maneuverable position.
About 31.50 inches. The inseam estimate is height × 0.45, so a 70-inch rider (road 57–59 cm, midpoint 58) has an estimated inseam of 31.50 in (80.01 cm) — but measure your real inseam before ordering.
Road 63–65 cm, mountain 19–21 in, hybrid 20–22 in. 76 inches is the bottom of the largest band (76–79 in), with an inseam estimate of 34.20 in (86.87 cm).
Try the smaller size first if you want agility, the larger if you want stability. The bands are half-open, so a height on a boundary belongs to the band above it — 70 inches is in the 70–73 band, not the 67–70 band — and the midpoint is the middle of the range.
Anything below your band. At 70 inches, the 54–56 cm road band is for riders 67–70 inches — 69.5 inches is the tallest height in that band, and 70 inches steps up to 57–59 cm.