Similar Triangles Calculator

Use corresponding side ratios to scale one triangle to another. The calculator assumes the sides are entered in matching a, b, c order.

Last updated: June 2026 | By Patchworkr Team

Triangle 1 to Triangle 2 Scaling

Triangle 1

Math check: a'/a = b'/b = c'/c = k, and every known pair must agree on the same scale factor.

Result

Enter at least one corresponding pair of sides.

a'/a = b'/b = c'/c = k

If Triangle 1 has sides 3, 4, 5 and Triangle 2 has b' = 12, then the scale factor is 12 / 4 = 3.

The other Triangle 2 sides are 3 x 3 = 9 and 5 x 3 = 15, so the scaled triangle is 9, 12, 15.

This calculator assumes corresponding sides are entered in matching order. If the side order is not aligned, the scale factor will be wrong.

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