25×25 Sudoku Symbols: Numbers, Letters, and Candidate Notes
Understand the symbols used in 25x25 Sudoku and how to keep candidate notes readable on a giant grid.
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Get the iPhone App →Most 25×25 Sudoku puzzles use the numbers 1 through 25, but the exact symbol set can vary. The important part is not whether the symbols are numbers or letters. The important part is that there are 25 distinct values.
Common 25-symbol sets
- Numbers 1-25: the clearest format for most solvers.
- Letters A-Y: compact, but less familiar if you expect numeric Sudoku.
- Mixed sets: sometimes used by puzzle publishers to save space.
Why notation gets harder
In 9×9 Sudoku, candidate notes fit comfortably inside a cell. In 25×25 Sudoku, a cell can theoretically hold many more candidates, so full notation gets dense quickly. Use grouped notes, box-level scanning, and printed grids when possible.
A practical candidate routine
- Write only the likely candidates, not all missing symbols.
- Scan five symbols at a time: 1-5, 6-10, 11-15, 16-20, 21-25.
- Mark strong row and column restrictions before filling tiny notes.
- Use the editable 25×25 grid to test a symbol layout before printing.
If you are still learning large-grid symbols, read the Hexadoku symbols guide before moving up to 25 symbols.