Introductory
What can you check in free Sudoku solvers and learning tools?
Compare observations and unverified details about input, solving, ads and offline use in Sudoku Coach, SudokuWiki Solver and Sudoku Solutions on 2026-09-23.
- Written by
- DailySudoku editorial team (Object)
- Published
- 2026-09-23
- Updated
- 2026-09-23
Test method and the shared puzzle
On 2026-09-23, we observed three free solving and learning tools in Chrome without an account. We examined input, solution counts and difficulty displays, steps and hints, accounts, ads and offline use. Results we observed are distinguished from page descriptions. The Chrome version and the versions of Sudoku Coach and Sudoku Solutions are unverified.
The shared test puzzle H is a hard puzzle with 28 givens. In the 81 digits below, 0 represents an empty cell. For Sudoku Solutions, we replaced every 0 with a dot .. We could not enter H directly into SudokuWiki.
010050000000000428080007100000030500007008300030600004341080000000071200572004003
Sudoku Coach
We pasted the 81 digits into Import → Text. The puzzle string then appeared in the URL, allowing it to be shared as a link. The summary showed 1 solution, 28 givens, difficulty indicators of approximately SE 4.5 and HoDoKu 642, «Fiendish (7)», and a technique bar with colored segments.
In Summary Mode, we navigated forward and backward from step 1/58. All candidates appeared on the grid from step 2. This observation does not establish a separate hint format or the range of explanations for other puzzles.
We used it without an account; registration and login were optional. There were no ads on the observed screen, and there was a support link. The page displayed a message saying the web app was installed and could be used offline; actual operation with the network disconnected is unverified.
SudokuWiki Solver
We confirmed Version 2.71.1 and a page modification date of 2026-09-20. The Chrome extension denied domain permissions for clicks and screenshots, so we could not enter puzzle H directly. The following describes page text, not results from running H.
The page describes entering cells directly or loading an example. A URL with the 81 digits after ?bd= showed an empty grid during observation. Solution Count is described as a button that counts solutions by brute force, but the solution count and difficulty result for H are unverified.
The page describes Take Step, 42 selectable strategies, a solve path excluding unchecked strategies, and hint options for no hints, strategy only, pattern only or eliminations only. We viewed the page while logged out. Ads are unverified because we could not view the screen; offline use is also unverified. The page states that use is personal and non-commercial only.
Sudoku Solutions
Input uses cell clicks or a string pasted into Seed. Empty cells had to be dots .: zeros were entered as the number 0 instead. Load retrieves a saved puzzle by its identification code. After entering H with dots and running Rate Difficulty, the remaining empty cells were rated «Hard».
The page describes solving the whole grid, part of it or one cell; Check for validity and a single solution; Hint for the next cell or a candidate to remove; and candidate generation and editing. The solution count for H and step-by-step explanations are unverified. We clicked Hint, but no hint text appeared during this observation, so its format is unverified.
We used it without an account and saw no ads on the observed screen. The cookie notice had only a Got it! button, which we did not press. Offline use is unverified.
Comparison of observed items
| Item | Sudoku Coach | SudokuWiki Solver | Sudoku Solutions |
|---|---|---|---|
| Input | Used 81-digit paste | Only input and example instructions checked | Used Seed with dots for empty cells |
| Count and difficulty | Displayed 1, SE about 4.5, HoDoKu about 642, Fiendish (7) | Count button described; H results unverified | Check described; H rated Hard, count unverified |
| Steps and hints | Navigated 58 steps; separate hint format unverified | Only step and hint options described | Solving and Hint described; hint format unverified |
| Account | Used without an account | Viewed while logged out | Used without an account |
| Ads | None on the observed screen | Unverified | None on the observed screen |
| Offline | Availability message displayed; operation unverified | Unverified | Unverified |
| Limits | One puzzle; explanation coverage cannot be generalized | Could not enter H directly | No hint text appeared |
Shared limits and scope
This record reflects 2026-09-23. Tools can change, and ad observations apply only to the screens seen at that time. HoDoKu was excluded because it is an installable Java program requiring a download. This observation was limited to three tools and a single puzzle, H. We did not test each tool with technique-specific example grids. H was not entered into SudokuWiki. We assign no scores, rankings or recommendations and do not evaluate our own app.