Enter your current bar position and saddle height, and this works out which frames reach it, what stem each would need, and how they'd differ to ride.

If you don't know your numbers, measure the bike you ride now — bar clamp height and reach from the bottom bracket centre, and saddle height from the bottom bracket to the top of the saddle. Rough figures still tell you plenty.

Once you've plotted a position, click a frame on the chart to see the full build, then use the "Save or print this spec" button to keep it.

This is a starting point, not a fitting. If two sizes both work, or none of them quite does, that's the conversation worth having — and it's the interesting part of ordering a frame made to measure.