How to Make a Crossword Puzzle

To make a crossword puzzle, pick a theme and a few long theme answers, place them in a symmetric grid, fill the remaining squares with clean words, write a clue for every answer, then solve and edit it before you share or submit it. Newspaper-style grids use 180° rotational symmetry, a 3-letter minimum word length, and full interlock, so every white square sits in both an across and a down word. The steps below are the same ones working constructors follow.

What do you need before you start?

You need three things: a grid size, a word list, and a way to check your work.

• Grid size. Standard American puzzles are 15×15 (daily) or 21×21 (Sunday-size). If this is your first puzzle, build a 15×15. Smaller grids have fewer long answers, which makes theme placement harder, not easier.
• A word list. You need thousands of candidate entries, ideally with quality scores so the filler leans toward lively words. See crossword word lists.
• Software. You can do it on graph paper, but software handles symmetry, numbering, and finding words that fit a pattern. See free crossword construction software for options.

Step 1: How do you choose a crossword theme?

Pick a trick that generates 3 to 5 answers, then pick the answers. A theme is a consistent wordplay idea that links your longest entries. Common types:

Rules of thumb that matter for a themed puzzle:

1. Consistency. Every theme answer must follow the same rule. One that bends the rule breaks the puzzle.
2. Length symmetry. Theme answers that sit in matching positions across the grid (rotated 180°) must have the same length. A 10-letter answer in row 3 needs another 10-letter answer in row 13 of a 15×15.
3. Freshness. Search an answer database such as XWord Info to see whether your idea has run before. More on this in crossword theme ideas.

Write your theme answers down with their letter counts before you touch a grid. If you can't make the lengths pair up, change the theme, not the rules.

Step 2: How do you build the grid?

Place your theme answers first, then add black squares to make the rest fillable. A 15×15 grid has 225 squares. Standard American grids follow these rules:

• 180° rotational symmetry. Turn the grid upside down and the black-square pattern is identical. In Gridsmith, symmetry is applied automatically when you place a block.
• 3-letter minimum. No answer shorter than three letters.
• Full interlock (connectivity). You can walk from any white square to any other white square without crossing a black square.
• No unchecked squares. Every white square belongs to both an across and a down answer.
• Moderation with black squares. Fewer blocks means longer, harder-to-fill words. Details and word-count limits are in crossword grid rules.

A workable order: put in the theme answers, add symmetrical blocks to separate them, then add blocks around the edges and corners to create manageable spaces. Avoid stacking theme answers directly on top of each other unless you want a very hard fill.

Step 3: How do you fill a crossword grid?

Fill the hardest spaces first, usually the corners and anywhere two long answers cross, and check every crossing as you go. Fill is everything that isn't a theme answer, and it separates a puzzle that feels polished from one that feels like a chore.

1. Start with the tightest region. Corners with a cluster of long entries run out of options quickly, so settle them early.
2. Use ranked candidates. Look at the words that fit a pattern like S_A_E and take the best-scoring one, not the first.
3. Avoid weak entries. Obscure abbreviations, partial phrases ("A TO Z"), and old crosswordese ("ESNE") annoy solvers. A few are tolerable. A dozen are not.
4. Watch crossings. Two obscure words crossing at one letter create a "Natick": a square a fair solver can only guess. See the glossary.
5. No duplicates. Don't repeat an answer anywhere in the grid.

Gridsmith's fill-assist ranks suggestions for the active slot that agree with every crossing, and you can autofill one word or ask the solver to try the whole grid. Filling a completely blank 15×15 from scratch is the hardest case and can be slow, so it works best after your theme and blocks are set. See crossword autofill and crossword fill tips.

Step 4: How do you write crossword clues?

Write each clue to be accurate first, then fair, then (if you can) clever. Clues should match the answer's part of speech and tense, and a "?" at the end signals wordplay.

• Match the answer. A plural answer needs a plural clue. A past-tense verb needs a past-tense clue.
• Don't repeat the answer. A clue for BAKERY can't contain "bake" or "baker".
• Calibrate difficulty. Early-week puzzles use straightforward definitions. Later-week puzzles use misdirection. The same answer might be "Place for rolls" (Saturday) and "Shop with loaves" (Monday).
• Write theme clues first. They carry the joke, so spend your effort there.

More examples in crossword clue writing.

Step 5: How do you test and edit your crossword?

Solve it cold, then have someone else solve it. After a few days away from your own puzzle you will see problems you missed.

Check the following:

• Does every theme answer follow the rule?
• Are there any Naticks or crossings that need a trivia fan to complete?
• Do any clues give away other answers, or share a word with their own answer?
• Are the answers in the long slots interesting?
• Are the stats reasonable (word count, number of blocks, no unchecked squares)?

A tester who is not a constructor is worth more than a second pass from you. Ask them where they got stuck and where they smiled.

Step 6: How do you share or publish a crossword?

Export it in the format your audience uses. Solvers commonly use Across Lite (.puz) files, and editors often specify a format. Gridsmith exports puzzles as JSON for free and, with Gridsmith Plus, as .puz or print-ready PDF. Compare formats in crossword file formats.

If you want to be paid, submit to a publication that accepts outside constructors. See the NYT crossword submission guide for how that works and which other outlets exist. A publication generally wants a puzzle that has never been published elsewhere, so don't post it publicly first.

Frequently asked questions

How long does it take to make a crossword puzzle?

A first 15×15 usually takes several hours to a few days, mostly spent on the fill and on rewriting weak spots. Experienced constructors can build a themed grid faster, but editing still takes time.

Can I make a crossword puzzle for free?

Yes. Several browser and desktop tools are free, including Gridsmith, which lets you build, fill, clue, and save unlimited puzzles at no cost. Paid features in Gridsmith are .puz export/import and print/PDF output.

What size should my first crossword be?

Start with a 15×15 themed puzzle. It's the standard daily size and the size most outlets expect.

Do crossword grids have to be symmetric?

Standard American puzzles use 180° rotational symmetry, and most publications expect it. Some outlets and puzzle types allow other patterns, but if you're unsure, use rotational symmetry.

Should I fill the grid by hand or with software?

Hand-filling teaches you the craft, but software finds fits far faster. Most constructors use software for lookup and constraint checking while making the creative decisions themselves.