Number Pyramid Generator

What you can do with this number pyramid generator

A number pyramid, also called an addition pyramid or sum pyramid, is a triangular logic puzzle where each cell holds the sum of the two cells immediately below it. Solvers fill in the missing numbers by working up, down, or across the rows using addition and subtraction. This generator builds custom worksheets with blank cells distributed according to your chosen difficulty level, then bundles them into a single PDF ready for the classroom, home, or puzzle club.

You control the number of rows (which dictates overall size and complexity), the range of starting numbers, the proportion of cells left blank, and how many separate puzzles appear on each sheet. An optional answer key appears on a separate page at the end of the document.

Small and large pyramids

The rows setting is the main difficulty control, and the two presets this page replaces sit at either end:

• Small pyramid — 4 rows, easy, six puzzles per PDF, large cells. Suits Key Stage 1 and anyone still writing big.
• Large pyramid — 7 rows, hard, four puzzles per PDF. A seven-row pyramid needs twenty-eight cells filled and the arithmetic compounds up the layers.

Rows matter more than the difficulty setting does: each extra row adds another layer of additions that depend on everything below it, so an error near the base propagates all the way to the top. That is what makes the large version genuinely harder rather than merely longer.

Turn on include solutions either way — with a propagating error, a child cannot tell where they went wrong without the answer to compare against. Ready-made PDFs of both sizes are in the gallery below.

Who number pyramids are for

Teachers

Print a stack of unique pyramids for morning warm-ups, timed drills, or homework packets. The adjustable difficulty means a single tool serves year three through year six without switching resources.

Parents and homeschoolers

Generate fresh puzzles on demand for maths practice that feels less like a worksheet and more like a game. The optional solutions page lets you check answers quickly or let older children self-mark.

Puzzle enthusiasts

If you enjoy Sudoku or KenKen, number pyramids offer a similar logic workout in a different shape. The hard setting produces puzzles that require trial, error, and backtracking.

What you can customise

• Rows: typically 3–7; more rows mean a taller pyramid and more cells to solve.
• Difficulty: Easy fills the entire bottom row and uses small numbers (1–9); medium hides more cells and raises the range to 2–15; hard blanks out up to 65 per cent of cells and uses numbers from 5 to 30.
• Puzzles per page: pack multiple pyramids onto a single sheet or dedicate a full page to one large puzzle.
• Cell size: toggle large cells for younger children or smaller handwriting.
• Solutions: include or omit the answer key on a separate page at the end of the PDF.

How to use the tool

1. Select the number of rows. Start with four if you are new to pyramids.
2. Pick a difficulty level that matches your audience: easy for ages 7–9, medium for ages 10–12, hard for confident solvers or adults.
3. Choose how many puzzles you want on each page (one large pyramid or two to four smaller grids).
4. Decide whether you need an answer key; tick the solutions box if you do.
5. Click generate and download your branded PDF.
6. Print on A4 or US Letter paper. The layout adjusts automatically.

Worked classroom example

A year-five teacher wants twenty different pyramids for a Friday challenge. She sets rows to five, difficulty to medium, and puzzles per page to two. She ticks the large-cells option because her classroom printer sometimes produces faint lines, and she includes solutions so her teaching assistant can mark the work during lunch.

The generator produces a ten-page PDF: pages one through ten each carry two unique pyramids, and page eleven holds all twenty answer grids in miniature. She prints fifteen copies, holes-punch the stack, and drops it into the maths station. Pupils who finish early grab a sheet, solve one or both pyramids, then check their work against the key pinned to the noticeboard.

How the algorithm works

The generator starts by picking random integers for the bottom row within the difficulty range, then calculates every cell above by summing pairs. Once the full solution exists, it selectively blanks out cells. Always leaving enough givens in each row to guarantee a logical solution path. Easy mode reveals the entire base; medium and hard modes hide progressively more cells, including some in the bottom row, forcing solvers to work bidirectionally and use subtraction to back-calculate missing values.

Designed for A4 and US Letter printing

Every PDF produced by this tool fits standard home and school printers. The layout engine detects your paper size and adjusts margins, cell spacing, and puzzle placement so nothing overflows or requires manual scaling. Print directly from your browser or save the file to print later. Both workflows produce identical results.

Notes and limitations

• The generator does not support custom starting numbers or fixed apex values; all puzzles are randomly seeded.
• There is no option to export puzzles as editable Word documents or plain-text files. Output is PDF only.
• Cell size and font are fixed within each difficulty tier; you cannot manually override typeface or border thickness.
• The tool does not verify uniqueness across separate generation sessions, so clicking generate twice may occasionally produce similar (though rarely identical) puzzles.