Evaluate Sudoku Puzzle Difficulty - How easy or hard is it?

A sudoku puzzle can be very easy, extremely hard, or somewhere in between, depending on the techniques required to solve it. This page estimates the difficulty level of a given puzzle based on the difficulty of the strategies that must be used to solve it. Enter a puzzle string below (see the main sudoku page and look above the puzzle for an example) and click Grade Puzzle to find out the estimated difficulty level.

Sudoku Difficulty Estimator

Enter a sudoku string (see example):