Stem Comparison Tool — Reach & Rise Calculator

Reach is the horizontal distance from the steerer clamp center to the handlebar clamp center. It directly determines how far forward your hands are relative to the headset. A longer reach stretches you out more; a shorter reach brings you upright. This is the most influential stem dimension for bike fit.

Rise is the vertical distance from the steerer clamp center to the handlebar clamp center. A positive rise lifts the bars above the headset; a negative rise (most road stems) drops them below. This affects your torso angle and lower-back load. Rise does not account for spacers under the stem — add those separately.

Most threadless stems can be mounted upside-down on the steerer. Flipping inverts the angle: a −6° stem becomes effectively +6°, raising the handlebars and slightly reducing reach. This is a free adjustment — no new parts needed, just an allen key. Use the flip toggle above to compare both orientations.

Enter your current stem in Setup A, then adjust Setup B with a stem you're considering. The visualization overlays both stems to the same scale from the same origin. The delta table shows the exact change in reach and rise — e.g., switching from a 100mm −6° to a 110mm −6° stem adds +10.0mm reach and −1.0mm rise.

As a rule of thumb, most riders can feel a difference of ≥5mm in reach. A 10mm change is significant — you will notice it in how the bike handles and where your weight sits. Changes under 3mm are typically undetectable in normal riding, though they matter for precision fitting in competition. Rise changes are less sensitive: the same 10mm vertical shift is usually less noticeable than 10mm of horizontal reach.