Free printable kakuro puzzles and tools

Number Crossword Generator (Crossword Number Fill-In)

Make number fill-in puzzles: place every number from the list into the grid so all crossings agree. Print them or play on screen.

A number crossword is a crossword-shaped grid with no clues, where you fit a list of numbers into the white squares. This free generator makes printable number crossword puzzles in your browser, and you can also play them online without printing anything.

There is no sign-up. Pick a grid size from 7 x 7 to 13 x 13, choose a difficulty, and make between 1 and 6 puzzles at a time. Nothing is uploaded or sent to a server.

Each puzzle card has an answer toggle, and you can print the puzzles with or without answers. The Copy link button saves your settings so you can get the exact same puzzles again later.

How to use the number crossword generator

  1. Set Grid size to 7 x 7, 9 x 9, 11 x 11 or 13 x 13. The default is 9 x 9.
  2. Set Difficulty. Easy uses numbers of 2 to 4 digits, Medium up to 5 digits, and Hard up to 7 digits.
  3. Set Number of puzzles from 1 to 6.
  4. Leave Allow a starter number on, or turn it off if you want puzzles that need no help to start.
  5. Choose Paper: Letter or A4.
  6. Click Generate. Each click makes a new random batch.
  7. On each card, read the number list. The numbers are grouped under headings such as “3 digits” and sorted from smallest to largest.
  8. Click Show answer to see the solution, or Play on screen to fill in the grid yourself.
  9. Click Print puzzles only or Print puzzles + answers.

On screen, click a square and type digits. Arrow keys move the cursor, and Space or Enter switches between across and down. Backspace or Delete erases a digit. On a touch screen, use the 0-9 pad. Check marks wrong digits, and Reveal cell, Reveal all and Clear grid are there when you need them. A number is crossed out in the list once it appears complete in the grid.

Each puzzle prints on its own page, and you can choose Save as PDF in the print window to keep a copy. Progress is not saved if you reload the page, so use Copy link if you want to return to the same puzzles.

What is a number crossword?

A number crossword, also called a number fill-in or cross number puzzle, is a crossword-shaped grid with no clues. You get a list of numbers grouped by how many digits they have, and you must place every number once, across or down, so that all the crossings agree.

The grid follows the same shape rules as a normal crossword. The black squares are symmetric when the grid is turned 180 degrees, all white squares connect to each other, and every white square belongs to an across number and a down number of two or more digits. Each number fills one unbroken run of white squares exactly, so a 4-digit number needs a run of four squares.

Digits 0 to 9 can be used, and a digit can repeat inside one number. No number starts with 0, and no number appears twice in the list. Where two numbers cross, they share one square, so that digit must match in both.

How do you solve a number crossword?

Start with the lengths that have only one or two numbers, which are often the longest numbers. Place them in the grid, then use the digits they fix at each crossing to narrow down the shorter numbers.

When two numbers of the same length could go into the same slot, look at a digit position where they differ. Check which candidate matches the crossing entry in the other direction, and place the one that fits. Work in small steps: place one number, check its crossings, then move on.

If a card shows a starter number, write it into the grid first, because it is already fixed. Use it as your first anchor and work outward from there. Cross numbers off the list as you place them; when you play on screen the tool does this for you, so the numbers still to place are easy to see.

Frequently asked questions

Can I play the number crossword online?

Yes. Click Play on screen on any puzzle card to fill in the grid in your browser. Progress is not saved if you reload the page, so finish in one sitting or print the puzzle instead.

Are the answers included when I print?

Only if you choose Print puzzles + answers. The answer grids are added after the puzzles, four per page. Six puzzles give 6 pages without answers and 8 pages with them.

Does every puzzle have only one solution?

Yes. The generator fills the grid with random digits, and a solver counts the solutions before the puzzle is shown. If you turn off Allow a starter number, only puzzles that are unique without a starter are made.

What is the starter number?

When the list alone would fit the grid in more than one way, one number is written into the grid in advance, and the card says “Starter number … is already in the grid.” In testing, a starter was needed in about 71% of 7 x 7 Easy puzzles but rarely (0 to 9%) on 9 x 9 and larger grids.

How many numbers are in a puzzle?

A 7 x 7 puzzle has about 18 to 24 numbers. A 9 x 9 Easy puzzle has about 40. A 13 x 13 Easy puzzle has about 68, roughly 30 two-digit, 21 three-digit and 16 four-digit numbers.

How is a number crossword different from kakuro?

In kakuro, the clues are sums and you choose digits from 1 to 9. In a number crossword, the numbers are given and you work out where each one goes, using digits 0 to 9.