Logic Puzzles
deduce · place · solve
11 Puzzles · Auto-generated · Free

Logic Puzzles

Number-placement, deduction and grid-shading challenges. Every puzzle is generated fresh — no two games are ever the same. Four difficulty levels from Easy to Expert, with step-by-step solvers for every game.

All logic puzzles here are completely free, require no sign-up and work on any device. Use the Send to Solver button inside any game to get a step-by-step explanation of the solution.

Number Placement
🔢
Sudoku
rows · columns · boxes
Fill the grid so every row, column and box contains each digit exactly once. Four grid sizes from beginner 4×4 to expert 12×12.
4×4 – 12×12Easy → Devilish
▶ Play ⊞ Solver
➕
Calcudoku
cage arithmetic · deduce
Each cage must reach its target using the given operation. Try Operators Hidden mode — you must deduce both the digits and the operation.
4×4 – 9×94 operator modes
▶ Play ⊞ Solver
☠️
Killer Sudoku
cage sums · unique digits
Sudoku rules plus dotted cage constraints — digits in each cage must be unique and sum to the cage's target. No operators given.
9×9Easy → Devilish
▶ Play ⊞ Solver
✖️
Kakuro
cross-sums · 1–9 · no repeats
Like a crossword but with digits. Each run of white cells must sum to the clue and use each digit only once. Pure additive logic.
Cross-sumsDigits 1–9
▶ Play ⊞ Solver
↕️
Futoshiki
inequality constraints · order
Fill a Latin square where inequality signs between adjacent cells must also be satisfied. Combines Sudoku logic with ordering constraints.
5×5 – 9×9Inequalities
▶ Play ⊞ Solver
✨
Magic Sum
row & column sums
Each row and column has a given sum target. Deduce which digits fill the grid to satisfy all the totals simultaneously.
Row & col sumsEasy → Devilish
▶ Play ⊞ Solver
−
Magic Difference
anchor minus each value · edge target
Subtract each value in a row or column from its anchor cell — the running result must equal the edge target. Toggle negative targets for added depth.
3×3 – 6×6Negative targets optional
▶ Play No solver
×
Magic Product
multiply every row and column
Fill the grid so every row and column multiplies to the edge target. Factorisation thinking — a completely different mental mode from addition.
3×3 – 6×6Factorisation
▶ Play No solver
÷
Magic Division
divide from anchor · successive quotients
Divide each row and column from its anchor cell sequentially. Toggle decimal targets when you want results that aren't whole numbers.
3×3 – 6×6Decimals optional
▶ Play No solver
±×
Magic Mixed
rows ≠ columns · choose your operations
Choose a different arithmetic operation for rows and columns. 10 valid combinations from Sum/Product to Division/Difference — each creates a completely different puzzle feel.
3×3 – 5×510 op combos
▶ Play No solver
✦
Magic Path
number path · 52 rules · fractions & decimals
Connect all numbers matching a math rule in one continuous path. 52 categories across integers, primes, sequences, divisibility, decimals, fractions and percentages. 4×4 up to 12×12 grid.
4×4 – 12×1252 categoriesEasy → Devilish
▶ Play No solver
🔗
Number Snake
connected path · 1 to N
Connect the given numbers so that 1, 2, 3 … N form a single unbroken chain. Each number connects to the next by an orthogonal step.
5×5 – 10×10Path logic
▶ Play ⊞ Solver
Grid Shading & Loop Puzzles
◼
Hitori
shade · no adj · stay connected
Shade cells so no number appears twice unshaded in any row or column, no two shaded cells touch, and all unshaded cells remain connected.
5×5 – 9×9Shading logic
▶ Play ⊞ Solver
🌊
Nurikabe
islands · river · no 2×2
Divide the grid into white islands and a black river. Each island contains exactly one numbered clue equal to its size. The river is one connected body with no 2×2 blocks.
5×5 – 9×9Island logic
▶ Play ⊞ Solver
⬜
Pearl Path
closed loop · black & white pearls
Draw a single closed loop through every pearl. The loop must turn at black pearls and go straight through white pearls — with a turn adjacent to each white pearl.
5×5 – 12×12Loop logic
▶ Play ⊞ Solver