Measure the effective rim diameter (ERD) with the nipples and washers you’ll use. Enter the hub flange dimensions and lacing pattern for each side, then read the left and right spoke lengths in step 5. No account is required.
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Calculator questions
How does the calculator load rim, hub and nipple data?
The calculator loads its component index when the page opens. Once you choose a part, its dimensions and manufacturer source appear in that step and again under Calculation inputs, so you can compare them with current manufacturer documentation before building a wheel.
Can I calculate with a component that is not listed?
Yes. In the rim, hub or nipple step, choose “Not listed? Enter the measurements yourself” and type in your measured dimensions. Imported SpokeLab wheels open as custom entries, so every value can be checked before you use the result.