100 Free Medium Sudoku Printables

Ready to move beyond easy grids? I've put together 100 free medium Sudoku printables for solvers who know the rules and want more practice with pencil marks and logical deductions. Each puzzle has one large grid per page and a separate solution. Print any puzzle or save it as a PDF. All free, no signup required.

Starting grid for Medium Sudoku Puzzle 001, with room for pencil marks

To print or save a puzzle: Select a numbered Puzzle link, then choose Print This Page. Select your printer or a PDF option in the print window. The Solution link beside each puzzle opens its matching answer key. Puzzle and solution pages open in a new tab.

Every puzzle has exactly one solution and a verified Medium rating in HoDoKu 2.2.0 using its default settings. None can be finished with singles alone. Their checked solution paths use singles along with techniques such as locked candidates, pairs, or triples, without guessing.

The five groups help you find a puzzle number; they are not a difficulty ladder. You can also choose Easy Sudoku Printables or Hard Sudoku Printables. Below the puzzles, I explain how I checked the Medium rating and walk through a locked-candidate example from Puzzle #009.

Choose a Medium Sudoku Puzzle

How I Check and Rate These Medium Sudoku Puzzles

I used Cross+A and HoDoKu to generate this collection, then checked every puzzle against the same standard. A generator's own difficulty label was only a starting point. Here is what I verified before including a puzzle:

Exactly one solution. An independent solver searched each grid to establish that it has one solution, and that the separate answer key matches it.
A consistent Medium rating. All 100 received a Medium rating in HoDoKu 2.2.0 with its default settings. This is the same version and configuration used to check my Hard collection.
A step beyond singles. A separate singles-only check stalled on every puzzle. Simply filling a square with its only candidate, or finding a number's only available position in a row, column, or box, is not enough to finish these grids.
A complete logical solution path. HoDoKu solved every puzzle without brute-force or template-search fallback. I also checked for exact repeated grids within the collection and against my saved Easy and Hard puzzle sources.

For experienced solvers: the recorded paths use singles, pointing or claiming locked candidates, and two- or three-cell subsets such as pairs and triples. The mix varies by puzzle. No X-Wing, wing, or chain technique appears in these recorded paths. That describes a verified way to solve the puzzles, not proof that every named step is unavoidable.

HoDoKu considers both the difficulty assigned to the techniques it uses and their accumulated score. Its settings can be changed, which is why I specify the version and defaults. Medium is a consistent label within this collection, not a universal difficulty measurement. A familiar pattern can make one grid feel much easier than another. The number of starting clues alone is not my difficulty test.

How to Solve a Medium Sudoku

The rules stay the same: fill each row, column, and outlined 3 x 3 box with the numbers 1 through 9, without repetitions. The printed starting clues stay in place. What changes is that you sometimes need to rule out a possibility before you can write another answer.

Collect the straightforward answers first. Scan rows, columns, and boxes for missing numbers. Fill a square when only one number can fit, or place a number when it has only one possible position in a unit. Medium puzzles still contain many of these simple moves.
Add complete pencil marks when you get stuck. For each empty square, note every number that is not already in its row, column, or box. Keep the notes small and the final answers clear. Missing a legitimate candidate can make a false pair or other pattern look convincing.
Check where a box's candidates line up. If every possible position for a number inside one box lies in a single row, that number can be removed from the rest of the row outside the box. The same works with a column. This is a pointing locked candidate; the worked example below shows one.
Look for a two-square pair. If two empty squares in the same row, column, or box both contain only 2 and 7, those two numbers are reserved for those squares. Remove 2 and 7 from other squares in that unit. You do not have to know which member of the pair is the 2 yet.
Return to singles after each elimination. Removing a candidate may leave a square with one possibility or give a number just one remaining position. Update the affected pencil marks before looking for another pattern.

Two useful extensions

Claiming works in the other direction from pointing. If all possible positions for a number in one row fall inside the same box, that number cannot go elsewhere in that box. The same reasoning works for a column.

A three-square subset extends the pair idea. Suppose three squares in one unit have candidate lists {2, 7}, {2, 9}, and {7, 9}. Those three squares must collectively use 2, 7, and 9, so other squares in that unit cannot use those numbers. Every candidate in those three squares must belong to that three-number set.

Work with a pattern you can explain. For a refresher on the rules and basic scanning, see Kevin Rush's Sudoku Instructions: How to Play and Win.

Worked Example: Locked Candidates in Puzzle #009

This position comes from Medium Sudoku #009 after 16 single placements. It is a partly solved grid, not the starting puzzle. To solve #009 without this hint, skip the example.

Count rows from top to bottom and columns from left to right. Pencil marks are shown only in the three highlighted squares. Other empty squares still have candidates; their notes are omitted to keep the diagram readable.

Partly solved Medium Sudoku 009. In the middle-left box, 7 can go only in row 4 columns 1 or 2, highlighted green. The orange square at row 4 column 8 has candidates 7 and 8, so eliminating 7 leaves 8.

Focus on the middle-left box. Its only possible positions for a 7 are the two green squares: row 4, column 1 and row 4, column 2. Their full candidate lists are {2, 7, 8} and {4, 7}. Neither is a single yet. Row 5 already has a 7. The box's remaining empty square in row 6 is in column 3, which also already has a 7.
Notice that both positions are in row 4. This box must contain a 7. Whichever green square gets it, that 7 will also occupy row 4. We do not have to decide between the two green squares.
Remove 7 from row 4 outside the box. The orange square at row 4, column 8 cannot also contain 7, because that would put two 7s in the same row.
Place the resulting single. The orange square's candidates were 7 and 8. Once 7 is ruled out, its answer must be 8.

This is a pointing pair, one form of locked candidates. The word "pair" refers to the two possible positions for the 7. It does not require the green squares to have identical two-number candidate lists. The key is that all possible 7s in the box lie in the same row.

For more examples, see HoDoKu's guide to locked candidates. The separate solution for #009 shows the completed grid.

What to Do When You Get Stuck

Check the pencil marks around your latest entries before searching for a new technique. Placing a number can remove a candidate from squares in three different units: its row, column, and box. Scan again for a single after updating them.

Then follow one number around the grid. In each box, ask whether its possible positions all lie in one row or column. In each row or column, ask whether they all lie in one box. Concentrating on one number can make these relationships easier to see.

Check pairs carefully. Two squares that both include 3 and 8 are not a two-square pair if one also has a 5. Likewise, two aligned candidates inside a box do not establish a pointing pattern if that number could also go in another row of the same box.

If a square has no candidates, or you have repeated a number in a row, column, or box, revisit your recent entries and eliminations. A short break or a different puzzle can help. The separate answer key is there when you want to check one square or compare your finished grid.

Printing Medium Sudoku or Saving It as a PDF

Open a numbered Puzzle link before printing. Each sheet has one 5.5-inch grid, with space for pencil marks. Its matching solution has the same three-digit puzzle number.

For a paper copy: Choose Print This Page, select your printer, and check the preview. Use portrait orientation. The sheet is designed for US Letter paper; for A4 or a clipped edge, choose your print window's fit-to-page setting.
For a PDF copy: Select the PDF destination in the same print window, often called Save as PDF or Microsoft Print to PDF. Save the puzzle and its solution separately, keeping their three-digit numbers in the filenames.
For a clean sheet: Turn off browser headers and footers if the preview adds a date, URL, or page number. The site's ads and navigation are excluded from the printable sheet.
To print several puzzles: Use Next Medium Sudoku Puzzle above the preview. The same link appears on solution pages, so you can print a puzzle and its answer key, then move directly to the next puzzle. Puzzle #100 and its solution return to this hub.

For smaller grids and fewer sheets, try my four-puzzles-per-page Sudoku collection, which includes several difficulty levels.

Common Questions

Are these medium Sudoku puzzles and answers free?

Yes. All 100 puzzles and their separate solutions are free to print or save as PDFs. No account, email signup, or payment is required.

What makes these Medium rather than Easy?

Every grid receives HoDoKu's default Medium rating, and an independent check confirms that none can be finished with singles alone. You will need at least one candidate elimination beyond those placements. The checked paths stay within singles, locked candidates, pairs, and triples.

Do medium Sudoku puzzles require guessing?

These puzzles do not. Each has a verified logical solution path. If you get stuck, a useful elimination may be available even when no new answer is obvious. The worked example shows how eliminating one candidate can lead to an answer.

Which puzzle should I start with?

Choose any number. The groups organize the collection; #100 is not necessarily harder than #001. Try #009 if you would like to follow its worked example, or choose another puzzle to avoid that hint. For more practice with the basics, visit my Easy Sudoku Printables.

Are Medium and intermediate Sudoku the same thing?

Publishers use those labels differently. Here, Medium specifically means HoDoKu 2.2.0's default category. If these patterns are becoming familiar, my Hard Sudoku Printables provide a collection checked against the same software's Hard category.

Can I download all 100 as one PDF?

This collection uses individual puzzle and solution pages. Use the PDF option in the print window to save the ones you want. The Next Puzzle link makes it easy to move through several in sequence.

May I copy or share these puzzles?

Yes. You may print and share copies for home, classroom, church, club, workplace, care-home, or activity-group use. Keep the copyright line in place, and do not sell the puzzles. You may also include a puzzle in a newsletter or other publication with this credit: "© Memory-Improvement-Tips.com. Reprinted by Permission."