Compare the geometry of multiple bikes or see the effects of tweaking your bike’s geometry. Modifications include changing fork travel or offset, mixing wheel sizes, installing an angleset or reach adjust headset, changing rear center length, or installing a different lower headset cup.

The fields near the bottom allow for additional inputs and calculated measurements for optional bike fit comparison, including cockpit dimensions and Rider Area Distance (RAD) calculations. 

Note that manufacturers usually round their measurements, so the calculated results such as wheelbase or effective top tube found here are shown with decimal places not shown on the official geometry table. Geometry tables have been found to be incorrect from the manufacturer. If you notice the calculated values in this calculator are drastically different than the published numbers, there’s a good chance you’re seeing an error in the manufacturer’s data.

Click here for a figure demonstrating the geometry measurements included in this calculator. Read this blog post for tips on entering mullet (mixed wheel) bikes into the original geometry column. 

The calculations rerun each time you update a cell. To keep things running a bit faster, calculations will not update while you are typing. Click outside of the cell to complete your entry.

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