Number Pyramid Solver

Number Pyramid Solver — Step by Step

Choose the rows and whether bricks add or multiply. Click a brick and type its number; leave unknown bricks empty. Then press Solve. Or play a generated puzzle and send it here with one click.

Number Pyramid Solver: rules, how to use it, tips

Fill every brick so that each one equals the sum (or product) of the two bricks directly below it.

The rules

Bricks are stacked so each one rests on two bricks below.
In an addition pyramid, each brick equals the sum of the two below it.
In a multiplication pyramid, each brick equals their product.
Given bricks can’t be changed.

Using the solver

Type the bricks you know (or press Sample).
Press Solve and step through each brick: adding up, taking away, and algebra when two bricks are missing side by side.

Tips

Work up. Two bricks side by side give the one above them: add them.
Work down. A brick and one of its supports give the other: subtract (or divide).
Look for triangles. Every brick and the two below make a little triangle — any two numbers in it give the third.
Algebra. If two neighbouring bottom bricks are missing, call one ‘a’ and write the others in terms of it; the top brick gives an equation.

The full guide, with a worked example and common mistakes: How to play Number Pyramid.

Questions

Which age is it for?

3-row addition pyramids suit ages 5–6; 5-row and multiplication pyramids suit 8–11; algebra pyramids suit 11+.

Can bricks be negative?

Not in generated puzzles; the solver accepts negative numbers.

Is there always one answer?

Yes — every puzzle here is checked to have exactly one solution.

How do I check a pyramid from a worksheet?

Open the Number Pyramid Solver, type the bricks you know and press Solve.