Easy Kropki Sudoku

Black dots signal a doubling relationship; white dots mean consecutive digits. Unmarked pairs carry equally powerful information. Free online.

Easy Medium Hard Expert

New to Kropki Sudoku? Black dots mean one digit is double the other; white dots mean consecutive digits. No dot means neither applies. Start here.

6
8
9
7
3
3
4
3
5
7
4
6
5
2
7
6
4
3
6
2
7
7
8
5
9
1
2
7
8
6
3
3
8
4
2
7
1
2
Mistakes
0/3
Score
-
Time
00:00
Try Medium →
Progress0%

What is Kropki Sudoku?

Difficulty
★★★☆☆
3/5
Constraint Type
Cell Relationships
Typical Givens
18–24
Avg. Solve (Easy)
8 min

Solving Techniques for Easy Level

Technique Description Level
White Dot Pairs White dots mark consecutive digit pairs: (1,2), (2,3), …, (8,9). Cross-reference with row and column constraints. Beginner
Black Dot Pairs Black dots mark double-relationship pairs: (1,2), (2,4), (3,6), (4,8). Only these four combinations are valid. Beginner

Ready to go deeper? Try Medium Kropki Sudoku to unlock Intermediate techniques.

Average Solve Time by Difficulty

Easy
8 min
Medium
18 min
Hard
35 min
Expert
62 min
Want a full walkthrough of rules, strategies, and solving steps? How to Play Kropki Sudoku →

Frequently Asked Questions — Easy Kropki Sudoku

What is Kropki Sudoku?
Kropki Sudoku is a Sudoku variant where small dots appear between adjacent cells. A black dot means one of the two neighbouring digits is exactly double the other (e.g., 1 and 2, 2 and 4, 3 and 6). A white dot means the two digits are consecutive — they differ by exactly 1. Where there is no dot, neither condition applies.
What does a black dot mean in Kropki Sudoku?
A black dot between two cells means one digit is twice the other. The valid pairs with a black dot are: 1–2, 2–4, 3–6, 4–8. Note that 1–2 and 2–4 share the digit 2, so context determines which applies. Any pair not in this list cannot be separated by a black dot.
What does a white dot mean in Kropki Sudoku?
A white dot between two cells means the digits differ by exactly 1. Valid consecutive pairs are: 1–2, 2–3, 3–4, 4–5, 5–6, 6–7, 7–8, 8–9. Order does not matter — 3 next to 4 is the same as 4 next to 3.
What if there is no dot between two cells in Kropki Sudoku?
No dot is also a clue. If there is no dot between two adjacent cells, the two digits are neither consecutive nor in a 1:2 ratio. For example, 1 and 3 could sit next to each other with no dot, because they are not consecutive and 3 is not double 1. Use the absence of dots actively — it eliminates many candidate pairs.
How do I start an easy Kropki Sudoku?
Look for black dots first — they have fewer valid pairs than white dots. A black dot involving a small number (1 or 2) is very restrictive: a 1 can only pair with a 2 on a black dot, and a 2 can only pair with a 1 or a 4. Use these anchor points, then layer in the white dot constraints and standard Sudoku scanning.

More questions? See the full Kropki Sudoku guide.