Let us begin!

I recommend working with the Custom Grid System to use this method, while the Basic Grid System might work, it locks the width and height, so I wouldn’t recommend even trying that feature. Custom Grid System gives you complete freedom as width and height are not “bound” to each other. For my example, I’ll show you the exact grid we were working on when I met the design agency and then when I got back to my office, I found out! If I sound like a kid at Christmas eagerly waiting to open my present it’s because I know a lot of designers will make great use of this. I was demonstrating the grid on an A4 (210 × 297 mm) document.

Custom grid system

Width: 210 × 1 × 1 = 210

(Note that InDesign only gets the total sum of output: 210).

Modules: 210 / 1 = 210

Subdivisions: 210 / 50 = 4.2

This gives us 4.2mm for a subdivision width. Now, let’s see if we can match that value for the height of the subdivision. We can actually see if this is possible with a simple calculation: 297 / 4.2 = 70.714285714285714. Since it is not possible to enter anything other than integer values ​​in the subdivision, our closest values ​​will be 70 or 71.

70 = 4,243mm

71 = 4,183mm

In other words, unless we play with modules and a bunch of other things, the best we can do is get very close to 4.2mm and even if we play with the numbers, the chances are slim to none in most cases. . Will I ever be able to get a subdivision that exactly matches.

How can you create a document height that is still 297mm with a subdivision height of 4.2mm and have everything line up nicely? This is what I will show you. I can already imagine you saying: Why didn’t I think of this before (unless you haven’t discovered this method yet)?

Custom grid system

For this “trick” to work we need to make sure that the output height value is below the value we actually want it to be. For example, it cannot be 297 mm because then we will only be able to obtain a value that is really close to 4.2 mm but not exact. To prove my point, try setting the first height fields to 71 × 4.2 × 1 = 298.2 mm. Obviously that won’t work.

Try setting it to 70 instead: 70 × 4.2 × 1 = 294 mm.

Module: 294 / 1 = 294mm

Subdivisions: 294 / 70 = 4.2mm

Note

Don’t forget to press the Apply button; otherwise, the settings won’t be applied and could cause confusion when you hit Done and nothing happens.

So you’re saying to yourself: but I don’t want to have it set to 294mm, I want it to be 297mm. So here’s the “trick”, we’ll compensate for the missing part of the document using slug. Go to the Bleed and Slug section of the plugin and in the Lower field enter: 297-294. So you will get 3 mm. Now your grid will be perfectly square and the height will be whatever value you want it to be.

Note

Note that you should only do this with the bottom or outside and possibly the top of your document, but whatever you do, don’t use it on the inside of your document because when you work with facing pages or spreads, it will mess up your design.

PDF Settings

(Make sure Visible Grids and Guides is unchecked, in the General section.) Make sure to check: Include Slug Area, this will include the extra 3mm space at the bottom of the document to make it 297mm (294+3).

See the grid on the next page.

See video presentation here