Paper craft and learning models

Envelopes and buildable paper models

Make custom envelopes, cones, cylinders, pyramids, Platonic solids, Soma pieces, segmented spheres, and dimensional stars.

Envelope choices

Enter the finished envelope width and height, then choose standard, Euro, petal, or square side flaps. Fold lines stay separate from the cut outline in every download.

Exact flat developments

Cones, mitered cones, cylinders, pyramids, parallelepipeds, and the five Platonic solids use calculated edges and surfaces rather than traced pictures. The dimensional-star maker creates one buildable spike net per point plus its center caps.

The honest sphere exception

A smooth sphere cannot be made exactly from an unstretched flat sheet. The sphere tool therefore makes measured gores and reports the segment count, seam allowance, and maximum chord deviation instead of calling the result exact.