Here is a general conversion table showing how IGES entities are mapped to the ones of think3 when converting an IGES 3D model to the think3 format.
| IGES entity number |
IGES entity denomination | Corresponding think3 entity to which it is converted |
| 100 | Circular Arc | Arc |
| 102 | Composite Curve | Exploded into its component curves |
| 104 | Conic Arc | NURBS curve |
| 106 | Copious data | Exploded into its component lines |
| 108 | Plane | Plane |
| 110 | Line | Line |
| 112 | Parametric Spline Curve | NURBS curve |
| 114 | Parametric Spline Surface | NURBS surface |
| 116 | Point | Point |
| 118 | Ruled surface | Ruled surface |
| 120 | Surface of Revolution | NURBS surface |
| 122 | Tabulated Cylinder | Tabulated Cylinder |
| 124 | Transformation Matrix | Transformation Matrix (internally used by the program only) |
| 125(125_0) | Flash | Exploded into its component entities |
| 126 | Rational B-Spline Curve | NURBS curve |
| 128 | Rational B-Spline Surface | NURBS surface |
| 130 | Offset Curve | Offset Curve |
| 140 | Offset Surface | Offset Surface |
| 141 | Boundary | Trimming curves (for internal use only, not accessible as independent entities in the model) |
| 142 | Curve on Parametric Surface | for internal use only, not accessible as independent entities in the model. See also Trimmed Surfaces and the IGES entity #142. |
| 143 | Bounded Surface | Trimmed surface |
| 144 | Trimmed Parametric Surface | Trimmed surface |
| 150 | Block | Not converted |
| 152 | Right Angular Wedge | Not converted |
| 154 | Right Circular Cylinder | Not converted |
| 156 | Right Circular Cone Frustum | Not converted |
| 158 | Sphere | Not converted |
| 160 | Torus | Not converted |
| 162 | Solid of Revolution | Not converted |
| 164 | Solid of Linear Extrusion | Not converted |
| 168 | Ellipsoid | Not converted |
| 180 | Boolean Tree | Not converted |
| 182 | Selected Component | Not converted |
| 184 | Solid Assembly | Not converted |
| 186 | Manifold Solid B-Rep Object | Solid (if the Save/Load solid entities check box is selected in the IGES Conversion Options. Otherwise, solids are split into their component surfaces.) |
| 190 | Plane Surface | Plane |
| 192 | Right Circular Cylindrical Surface | Cylinder |
| 194 | Right Circular Conical Surface | NURBS Surface |
| 196 | Spherical Surface | NURBS Surface |
| 198 | Toroidal Surface | NURBS Surface |
| 202 | Angular Dimension | Exploded into its component entities |
| 204 (204_0) | Curve Dimension | Exploded into its component entities |
| 206 | Diameter Dimension | Exploded into its component entities |
| 208 | Flag Note | Exploded into its component entities |
| 210 | General Label | Exploded into its component entities |
| 212 | General Note | Not converted |
| 214 | Leader (Arrow) | Not converted |
| 216 | Linear Dimension | Not converted |
| 218 | Ordinate Dimension | Not converted |
| 220 | Point Dimension | Not converted |
| 222 | Radius Dimension | Not converted |
| 228 | General Symbol | Not converted |
| 230 | Sectioned Area | Not converted |
| 302 | Associativity Definition | Not converted |
| 304 | Line Font Definition | Not converted |
| 308 | Subfigure Definition | Exploded into its component entities |
| 310 | Text Font Definition | Not converted |
| 312 | Text Display Template | Not converted |
| 314 | Color Definition | Not converted |
| 320 | Network Subfigure Definition | Exploded into its component entities |
| 322 | Attribute Table Definition | Not converted |
| 402 | Associativity Instance | Not converted |
| 404 | Drawing | Not converted |
| 406 | Property | Not converted |
| 406 Form 1 | Definition levels Property | Layers |
| 408 | Singular Subfigure Instance | Exploded into its component entities |
| 410 | View | Not converted |
| 412 | Rectangular Array Subfigure Instance | Exploded into its component entities |
| 414 | Circular Array Subfigure Instance | Exploded into its component entities |
| 416 | External Reference | Not converted |
| 418 | Nodal Load/Constraint | Not converted |
| 420 | Network Subfigure Instance | Exploded into its component entities |
| 422 | Attribute Table Instance | Not converted |
| 430 | Solid Instance | Not converted |