A question that often comes up, is the font size that's used for puzzles that are generated with Puzzle Maker Pro.

Especially when you want to mark a book as Large Print on KDP/Amazon, you really want to know the font size in the books generated with Puzzle Maker Pro.

This is not an easy question to answer, because there are several steps involved, and additionally, not all fonts have the same size at a given font size. (Which has nothing to do with Puzzle Maker Pro).

In general, if you want to publish Large Print books, it also make sense to use a clear font like Arial, to improve readability. If you use a artful font with lots of embellishments, it may satisfy the requirements for Amazon, but still be hard to read for your target audience, resulting in negative reviews.

How are Fonts and DPI related to each other?

First, lets discuss font size and DPI.

DPI is an acronym for Dots Per Inch, and for print you’ll need 300 DPI. All Puzzle Maker Pro images are created at 300 DPI (unless you switch to 96DPI). You don’t have to worry about that.

Font size is measured in points, not in dots or pixels: One point is 1/72th of an inch. Large print, 16 points or larger, means 16/72th of an inch, which is 0.222″ (or larger).

Note: Different tools use different units. For example Microsoft Office uses points, while most image editing apps use pixels.

How do I create a puzzle book with Puzzle Maker Pro

Puzzle Maker Pro uses two steps to create puzzle books:

1. Create the puzzles,
2. Create the puzzle book from these puzzles.

Find out more about the two-step approach of Puzzle Maker Pro

How can you find out the font size that's used for a puzzle?

The font size that is used in your puzzles depends on the size of your puzzle, the puzzle type and the puzzle settings. Below you can see the method to find out your font size.

How to set the Puzzle Size

In puzzle Maker Pro, you can select how big you want your puzzle images to be. Starting at 300, up to 3000. With 300DPI that’s 1″ up to 10″.

How to calculate the font size for a puzzle type

The size of the characters that are used to print a puzzle, depends on the puzzle size you’ve selected.

Let’s take regular 9×9 sudoku as an example:

The total puzzle size (let’s say 2700 pixels) is split into 9 rows and 9 columns. Each row has a height of 2700/9, and each column has a width of 2700/9, which is 300 pixels. Which is 1″

Puzzle Maker Pro automatically calculates the font size for each square. By default it uses 80% of the height, leaving 10% on top and 10% at the bottom as margins. For some puzzle types you can modify this ratio, resulting in a different font size.

To calculate the font size, take 80% of 300 pixels, this is 240 pixels (numbers are rounded here). This is not yet the font size in points.

To go from pixels to points, we divide by 300 (300 pixels per inch) and multiply with 72 (72 points per inch). 240 / 300 * 72 = 57.6 points.

Summarized: A 9×9 sudoku puzzle, rendered to a jpg of 2700 pixels, will use a font size of 57.6 points.

However…

That only applies if you print the image at it’s actual size.

How does the font size change when creating a puzzle book from your puzzles?

When you create your puzzle book, the puzzle images will be resized, and usually the size will be reduced.

For example, let’s create a 6×9″ book interior with 0.5″ margins left and right. 6″ minus 0.5″ (left margin) minus 0.5″ (right margin) leaves 5″ for the puzzle.

5″ at 300 DPI is 1500 pixels.

Let's say we created a puzzle of 3000 pixels, resulting in a font size of 64 points.

You can easily see that it needs to be reduced by 50% (1500 / 3000). In which case the font also will be 50% smaller. 64 points / 2 = 32 points. Still a lot more than 16.

For the 9×9 sudoku puzzles, you’ll usually be fine, but for other sudoku puzzles, you’ll need to do the math, unfortunately.

What are the steps to determine the font size?

In most cases it's enough to approximate the font size, as long as it's clearly over 16 points.

Here are the steps:

1. Calculate the page body width, which is the trim size minus the margins. Example: an 8x10" book with .5" margins has a width of 7"

2. Divide by the number of puzzles in a row. Example: let's print 2 rows of 2 puzzles on each page. 7" / 2 = 3.5". For simplicity, we'll ignore the 0.1" padding between the puzzles.

3. Calculate the number of pixels for each square in the puzzle. This depends on the puzzle type. Example: For Sudoku 9x9, we can divide 3.5" by 9, that's 0.3889".

4. Calculate the font size in pixels for each square. This is 80% of the square size (with 10% padding). Example: 0.3889" times 0.8 = 0.311"

5. Calculate the font size in points from the font size in pixels: inches * 72 = points. Example: 0.311" * 72 = 22.4 points.

For some puzzles, for example Word Search and Bingo, you can further modify the font size for each font. In that case these calculations get a bit more difficult, but the slider for the font size also shows the percentage. You can use this percentage to calculate the resulting point size.