Bicycle spoke length calculator for iPhone and iPad

Wheel Builder

Calculate spoke lengths, review hub and rim geometry, save builds, and keep your wheel projects organized before you order spokes.

Download on the App Store Measurement guide Get support

$2.99 on the App Store. No accounts, ads, analytics, or tracking.

L/R spoke lengthsRounded order sizes plus raw values

Build CheckVisual cues before you order

Saved buildsPresets, notes, share, and search

Wheel Builder calculator screen with rim, lacing, and hub geometry fields

292 mmLeft and right

Build CheckReady to review

3-cross32 spoke disc wheel

Spoke math without the shop-note chaos.

Wheel Builder keeps the numbers that matter in one place: ERD, flange diameter, center-to-flange distance, spoke count, lacing, rim offset, spoke hole diameter, and saved wheel notes.

Calculate

Left and right spoke lengths.

Enter hub, rim, and lacing measurements to calculate side-specific spoke lengths with practical rounding options for ordering.

Review

Catch risky configurations.

Build Check highlights missing, unusual, or conflicting values so you can slow down before buying the wrong spokes.

Organize

Save the wheels you build.

Keep hub presets, rim presets, saved builds, notes, Spotlight search, JSON backup, sharing, and optional iCloud sync together.

Choose the wheel

Start from a hub preset, rim preset, or custom measurements.

Hub and rim

Enter geometry

ERD, flange diameter, center-to-flange, spoke count, lacing, and advanced offsets stay visible.

Measurements

Run Build Check

Review ready, warning, and needs-fix states before trusting the result.

Visual cues

Save and share

Store the build, duplicate it, search it later, or share a spoke order summary.

Order prep

Built around the way wheel projects really happen.

New hubs, reused rims, asymmetrical rears, test builds, and one-off repairs all need clean measurements and repeatable notes.

Wheel Builder calculator screen with spoke length results and build check — **Calculator and Build Check**Calculate, review, and keep the result visible while editing.

Wheel Builder presets screen showing hub and rim libraries — **Hub and rim presets**Keep common components ready instead of retyping every dimension.

Wheel Builder saved builds screen with search and saved wheel projects — **Saved wheel builds**Search, duplicate, recalculate, share, and back up project notes.

A cleaner bench for spoke length work.

Wheel Builder is made for people who want the calculation, the measurement sanity check, and the order summary in one native iPhone and iPad app.

Download on the App Store Read instructions Privacy

Offline-firstThe calculator works without an account or network connection.

Optional iCloud syncUse your Apple ID to keep presets and builds on your own devices.

Shortcuts and SpotlightFind saved builds and run calculations from Apple system tools.