Learn to solve hard sudoku without guessing in three months
Three months of one puzzle a day, plus a named library of techniques learned in the right order, takes you from "stuck on medium" to clearing hard puzzles with pure logic. About 30 hours total. You will not solve "diabolical" grids with chains and colouring. You will never have to guess on a newspaper sudoku again.
3 months · ~30 hours · solve hard puzzles by logic, no guessing
1.Cracking the Cryptic — learn to see the board
Cracking the Cryptic is the largest sudoku channel on YouTube; Simon Anthony, a former UK puzzle champion, narrates his exact thought process as he solves. Start with his beginner and "easy to hard" tutorial videos, then watch him solve real puzzles and pause to spot the next move yourself before he does. You are not memorizing — you are learning what a deduction sounds like. This is the fastest way to internalize scanning, candidates, and when a square is forced.
Free
Cracking the Cryptic on YouTube →2.SudokuWiki — the technique reference
When you hit a puzzle you can't crack, you need a named technique to look up — and SudokuWiki is the canonical catalogue, ordered easiest to hardest with interactive examples. Climb it in order: naked and hidden singles, then pointing pairs, then the X-Wing. Don't try to learn it all at once. Learn the next technique only when a stuck puzzle demands it. Each new pattern is a tool you'll reach for again and again.
Free
sudokuwiki.org strategy guide →3.Solve one puzzle a day, leveling up
Skill is reps. Solve one puzzle every day, on paper or in an app, and step the difficulty up only when the current level stops making you think. Pencil in candidates in the corners; that's not cheating, it's how everyone past easy solves. Move from easy to medium to hard as singles, then pointing pairs, then the X-wing each unlock a new tier. When you're stuck, find the technique on SudokuWiki — never guess. A guess that works teaches you nothing.
Free (sudoku.com or pencil and paper)
sudoku.com daily puzzles →If this doesn't fit you
If you'd rather have the techniques laid out as a structured written course than learn them from video, skip step one and use SudokuWiki's own strategy pages as your primary text, working top to bottom. Read each technique, then immediately find a puzzle that requires it on sudoku.com's harder tiers. Slower than watching Simon think aloud, but better if you learn by reading and doing rather than by watching.
Why this path
The bottleneck is that most people grind the same medium puzzles for years and never learn a single named technique, so hard puzzles look like magic. The fix is to learn techniques in difficulty order and force yourself to apply each on a real, stuck puzzle. Cracking the Cryptic teaches you to see; SudokuWiki names what you're seeing; daily solving wires it in. The discipline that matters most: when you're stuck, look up the technique — do not guess. Guessing is the habit that keeps people permanently mediocre.