Magic 15 · a little daily challenge

Free daily number puzzle

Can you make every line 15? Use each number from 1 to 9 once. Every row, column and both diagonals must add up to 15. Three numbers are already in place.

One small challenge. No clock to beat.

Nine squares. Eight lines. One target.

Fill the gaps, find the balance, then challenge a friend to the same grid. Your attempt stays on this page.

No signup. First-time players complete a quick eligibility check.

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1
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5
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9
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How to solve a 3×3 magic square

  1. Start with a row or column that already has two numbers. Subtract their sum from 15 to find the missing number.
  2. Check that the number is not already elsewhere in the grid. Each digit from 1 to 9 can appear only once.
  3. Use the centre five to find opposite pairs: 1 and 9, 2 and 8, 3 and 7, or 4 and 6.
  4. Check both diagonals as well as the rows and columns. A grid can have correct rows but still fail on a diagonal.

Try the reasoning: if a line contains 8 and 1, the missing number is 15 − 8 − 1 = 6. This is an example, not necessarily a clue in today’s layout.

Why does every line add up to 15?

The numbers 1 through 9 add up to 45. The three rows use all nine numbers, so equal row totals must be 45 ÷ 3 = 15. A magic square also requires its columns and diagonals to have that same total.

The centre is 5. One way to see why: the middle row, middle column and two diagonals total 60 together. They count every outside square once and the centre four times. That is the grid’s total of 45 plus three extra copies of the centre, so the centre must be (60 − 45) ÷ 3 = 5.

Daily play and extra practice

The daily layout changes at midnight UTC. Practice works through a finite set of 64 classic magic-square variants without repeating during this page visit until that set is exhausted. Layouts repeat across visits. Any valid solution that keeps the clues is accepted. Use a hint when you are stuck, or reset to try the same grid again.

There is no timer, public ranking, account requirement or score upload. Your entries clear when you leave or refresh. This is a recreational logic puzzle—not an IQ test or a medical assessment.

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