GEARSMITHGEARSOpen the builder →
⚙ PARAMETRIC DRIVETRAIN CAD · IN THE BROWSER

Design a production-ready
gearbox in minutes.

Pick a reduction. GearSmith solves the tooth counts, checks assembly and interference constraints, simulates the running gear train in 3D, and exports every part as STEP & STL — with a costed BOM and step-by-step assembly instructions.

Start building — it's freeNo account. No install. Runs entirely client-side.

⚙ Three architectures

Planetary (3–100:1 with auto two-stage compounding), cycloidal (6–60:1, balanced twin discs) and harmonic (30–160:1) drives — real involute profiles, hypotrochoid discs and elliptical wave generators.

▦ Feasibility solver

Every listed design satisfies the ring–sun–planet identity, the N-planet assembly condition, neighbor-clearance and minimum tooth-count rules. No impossible gearboxes.

▶ Live simulation

Spin the input and watch correct mesh kinematics — carrier ratios, cycloidal wobble, flexspline wave deformation — with exploded view and speed control.

⬇ Manufacturing pack

One zip, organized for the shop: print-compensated STLs with a print guide, nominal STEP solids with a machining guide, motor mount for 10 catalog motors or your own, costed BOM and assembly steps written for your exact design.