Exact circumference, ready to print
Custom Cylinder Net Generator
A cylinder net is one rectangle plus two matching circles. Set the radius and height, and the generator makes the rectangle exactly one circumference wide.
Advanced settings · layouts, labels & printing
Worked example
Cylinder example: radius 1.8 cm, height 4.5 cm
The side rectangle is 2π × 1.8 ≈ 11.31 cm wide and 4.5 cm tall. Add two circles of radius 1.8 cm. The total surface area is 22.68π ≈ 71.25 cm².
The rectangle width is the circumference, not the diameter. Both circular ends have diameter 3.6 cm.
Overlap only the glue tab. Overlapping the rectangular wall shortens the circumference and makes a narrower cylinder.
How to print and assemble
- Set the radius and height, choose A4 or Letter, and resolve any actual-size warning.
- Cut and gently curve the rectangle. Join its edges with the glue tab underneath.
- Fold the circular-end tabs inward and attach one end at a time. Let the seams dry before handling.
The geometry
Cylinder net formula
The rectangle is 2πr wide and h tall. The two circles each have radius r. Total surface area = 2πr² + 2πrh.
Quick answers
Frequently asked questions
What shapes make a cylinder net?+
One rectangle forms the curved wall, and two equal circles form the top and bottom.
Why is the rectangle 2πr wide?+
That width equals the circumference of each circular end, so the edges meet exactly when wrapped.
Why is my finished cylinder narrower than the radius I set?+
The rectangle is cut to exactly one circumference, so its two ends should meet edge to edge with the glue tab underneath. Overlapping the seam instead shortens the wrap and tightens the tube; thick card has the same effect.