Modeling · Intermediate

NURBS

Smooth surfaces defined by math curves, used for precise product design

Also called Non-uniform rational B-splines

What is NURBS?

NURBS, short for non-uniform rational B-splines, is a way of describing smooth curves and surfaces with math instead of flat faces. A few control points shape each surface, and it stays perfectly smooth at any zoom. NURBS is common in car, product and industrial design, where curves must be exact.

Think of it like this

NURBS is like a flexible ruler bent by a few pins: move a pin and the whole curve flexes smoothly, with no corners anywhere along it.

Where it fits in a 3D project

  1. Create
  2. Surface
  3. Rig
  4. Animate
  5. Render
  6. Export

Create: Building the shape: modeling, sculpting, scanning or generating it.

How NURBS works

  1. 01You place control points that roughly outline a curve.
  2. 02The software calculates a smooth curve that is pulled toward those points.
  3. 03Curves are joined or swept into smooth surfaces.
  4. 04For games or real-time viewing, the surface is converted into a polygon mesh.

NURBS vs subdivision surface

PropertyNURBSSubdivision surface
Built fromMath curves and control pointsA polygon cage, smoothed in steps
PrecisionExact, measurable curvesSmooth, but approximate
LayoutFour-sided patches stitched togetherAny shape of connected quads
Common inCars, products, CADCharacters, games, film

Choose NURBS when a curve must be exact for manufacturing; choose subdivision surfaces when the model will be textured, animated or used in a game.

Where NURBS is used

  • Car bodies and consumer product design
  • Parts that move from design into manufacturing
  • Smooth curves that convert to meshes at any detail level

Beginner tip

If a NURBS model is headed for a game engine or a web viewer, convert it to a mesh and check the result. The conversion settings decide how many faces you get.

Terms related to NURBS

NURBS FAQ

What does NURBS stand for?
Non-uniform rational B-splines. Non-uniform means the curve’s sections can be spaced unevenly, rational means each control point can carry its own weight, and a B-spline is a smooth curve built from joined pieces.
NURBS vs mesh: which should I use?
Use NURBS when you need exact, manufacturable curves, as in product and car design. Use a mesh for anything that will be animated, textured or run in a game engine, which covers most 3D art.
Can you convert NURBS to a mesh?
Yes. Most 3D and CAD apps can turn a NURBS surface into polygons, a step called tessellation. You choose how dense the mesh is. Converting a mesh back into clean NURBS is much harder.

Updated October 29, 2026 · Browse all 3D terms