Read the grid
Understand units, peers, givens, full houses, and crosshatching.
Take the first lesson →Learn with Orbace
See the next true thing.
Begin with the three rules, build a repeatable solving method, and then learn from the exact moment a difficult grid opens. Orbace connects clear lessons with replayable Su-Pu and one original expert study every week.
Start here
Sudoku in three rules.
- Place the digits 1–9 once in every row.
- Place the digits 1–9 once in every column.
- Place the digits 1–9 once in every 3×3 box.
Sudoku is not arithmetic. Each given digit creates restrictions, and every valid placement follows from those restrictions. A well-formed Orbace puzzle has one solution and does not require blind guessing.
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Your learning path
Build understanding in layers.
You do not need every technique before you play. Each stage adds one kind of observation while keeping earlier skills active.
Place certain digits
Recognize naked and hidden singles without guessing.
Study direct placements →Use candidates
Record possibilities accurately and update notes after every move.
Learn candidate discipline →Make eliminations
Use intersections, pairs, triples, fish, wings, and chains as evidence.
Study intermediate logic →Replay the reasoning
Use Su-Pu to find the pause, correction, and turning point in a solve.
Watch a sample replay →Practice with purpose
Choose packs by difficulty or the strategy you want to strengthen.
Browse Puzzle Packs →First lesson
How to read an empty cell.
Every empty cell belongs to one row, one column, and one box. Check all three before deciding what can remain.
1. Look across
Digits already in the row cannot appear again.
2. Look down
Remove every digit already used in the column.
3. Look nearby
Remove digits already used in the 3×3 box.
4. Conclude carefully
Place a digit only when one legal possibility remains—or when it is the only location for that digit in a unit.
Weekly Su-Pu Study · No. 01
The pointing pair that changed the entire grid.
This Hard puzzle appears to stop after the early singles. One box-line relationship removes a candidate, creates a hidden single, and begins a four-move cascade.
Why this solve is worth studying
Several candidate-rich cells attract attention, but the decisive relationship sits in a quieter box. The study reconstructs the position, explains the valid elimination, and compares the successful route with two common detours.
Main strategyPointing pair
Supporting logicHidden single and cascade
SourceOrbace Tea Moment
ReviewIn-house expert
How Orbace teaches
A hint should reveal logic, not erase it.
Orbace’s graduated hints protect the satisfaction of discovery.
Orient
Identify a promising row, column, box, or candidate.
Name
Identify the relevant strategy and recall its restriction.
Explain
Connect the candidates in plain language so the reasoning transfers.
Reveal
Show the move only at the final level, together with the reason.
Meet the in-house expert
The reasoning is reviewed by a person.
[Expert name], Orbace Sudoku’s puzzle analyst, reconstructs intended and alternative paths, checks every elimination against the published grid, and prepares the weekly Su-Pu Study.
Editorial standard
- Original analysis based on an Orbace puzzle or clearly licensed example
- Named byline, publication date, and revision date
- Accessible description of every important board state
- Clear distinction between demonstrated fact and expert interpretation
- Correction channel and visible update history
Replace the placeholder expert identity before publishing this section or enabling the profile link.
Orbace Journal
One useful idea every week.
The journal is the publishing engine behind Learn: original Su-Pu studies, strategy explanations, beginner guidance, puzzle craft, and reflections on Tea Moment play.
Learn from the turning point
Move-by-move expert analysis of interesting Hard, Expert, and Extreme solves.
Browse studies →Understand why it works
Plain-language lessons that connect a formal pattern to a real grid.
Browse strategy articles →Build a dependable method
Rules, scanning habits, candidates, and solving without blind guesses.
Browse beginner guides →See how puzzles are shaped
Validation, logical flow, turning points, and what makes a grid satisfying.
Explore puzzle craft →Make room for one quiet puzzle
Ideas for intentional daily play without attention pressure.
Read Tea Moment stories →Visit the Orbace Journal
Browse every published guide, study, and editorial category.
Open the Journal →Monday
Select and verify the featured solve.
Tuesday–Wednesday
Reconstruct the Su-Pu and draft the analysis.
Thursday
Expert and editorial review.
Friday
Publish the study and related practice path.
Questions
Learning Sudoku FAQ
Should I begin with articles or puzzles?
Play first when you know the rules. When you become stuck, learn one relevant idea, return to the grid, and explain the next valid move in your own words.
Do I need candidate notes?
Not for every puzzle. Use them when direct scanning stops and accuracy matters more than keeping the grid visually sparse.
What is the difference between Strategies and the Journal?
The Strategy Library is a durable reference organized by technique. The Journal publishes dated expert studies, examples, and new commentary every week.
How does Su-Pu help me learn?
A Scorecard summarizes the result. Su-Pu preserves the sequence, making it possible to revisit uncertainty, corrections, and the move that changed the grid.
一局一茶
Begin with one clear observation.
You do not need to see the whole solution. Find the next true thing, place it carefully, and let the grid change.