Calculation methods
The formulas, worked examples, assumptions and limits behind every tool.
Sudoku maker ↗
A shuffled valid solution is reduced one clue at a time; a bounded solver keeps a removal only if exactly one solution remains.
Example: Choose 44 clues and seed 2026, then regenerate: the same seed and clue target produce the same puzzle.
Clue count is not a rating of human difficulty. The actual clue count is reported if the requested target cannot be reached while keeping uniqueness.
Maze maker ↗
Depth-first search removes walls to form a spanning tree; the answer follows the unique path between the two openings.
Example: A 16 × 12 maze has 192 cells and 191 internal passages.
Supports 5–40 cells on each axis. Small cells may be hard to read at high grid sizes; export uses vector lines.
Word search ↗
Words are placed longest first with bounded randomized trials; overlaps are allowed only where letters agree.
Example: Try PLANET, COMET, ORBIT, STARS and MOON in a 14 × 14 grid.
Accepts 2–20 unique A–Z words, 2–18 letters each. A placement failure asks you to enlarge the grid or change the seed; words are never silently dropped.
Math worksheet ↗
Seeded integers generate each exercise. Subtraction stays nonnegative; division is constructed from an integer quotient and a nonzero divisor.
Example: With factor limit 12, division can include 48 ÷ 4 = 12; its dividend can exceed 12.
Supports 1–60 questions and factor limit 1–100. Exercises may repeat. The limit applies to generated operands for +, −, × and to quotient/divisor for ÷.
Units and numerical limits
Conversions use 1 inch = 2.54 cm, 1 mile = 1.609344 km, and 1 avoirdupois ounce = 28.349523125 g. Empty, non-finite, out-of-range and unsupported values are rejected. Displayed values are rounded; calculations retain precision. Input-specific limits are reported alongside the field when exceeded.