Illustrated ebooks for children
An illustrated children's ebook is the hardest digital book to get right, and it is the one where the format decision goes wrong most often. Most of what goes wrong later was settled in the first ten minutes, by choosing a format that cannot carry the book you wrote.
The one question that decides it
Do the words sit inside the art, or beside it?
Inside the art. In a picture book the text is placed in the composition — in the sky above the character, in the flat area the illustrator left for it, curving around a shape. Reflow pulls that text out of the picture and stacks it in a column above or below, and the relationship between words and image, which was the book, is gone. That is a fixed-layout job. Fixed layout: when the page is the design sets out the whole test and what the format costs.
Beside it. A chapter book or an illustrated middle grade novel is prose with drawings in it: one picture per chapter, a spot at a chapter opening, a map at the front. Cover the pictures and the story still reads. That book should be reflowable, with each image sitting between paragraphs, moving as the text around it moves.
Both mistakes are expensive, in opposite ways. A picture book forced to reflow separates the words from the art they were written for. A chapter book frozen into fixed layout takes away the reader's type size control for nothing, and a child learning to read is exactly the reader who needs it.
Everything below is the reflowable case, which is the book most children's authors are actually making.
Size the images for both ends of the type scale
The reader's chosen type size is the variable you cannot see. Your illustration has to work at the smallest setting, where the column is dense and a picture can dominate, and at the largest, where a full-width image and its caption fill the screen on their own and leave the reader a page with no story on it.
- Set width as a share of the column, not a pixel count. A width in pixels is a guess about a screen you do not own.
- Supply enough pixels to survive a high-density screen at full width, then let the reading system scale down. Scaling down looks fine; scaling up does not.
- Do not send a print-resolution file to an ebook. The illustration that is correct in the print interior is many times heavier than the screen edition needs.
- Open the finished file on a phone at the largest type size it offers. Ten minutes there finds most of it, and How your ebook actually looks on other people's devices is the wider version of the habit.
Captions belong to their image
A caption has to be bound to its picture as one unit, not left as the paragraph that happens to follow it. Loose, it drifts: the image ends one screen and the caption opens the next, where it reads as a sentence of the story. That matters more in a children's book than most, because the caption is often the joke, the label or the naming game.
Alt text is not optional here
Alt text matters more in children's publishing than anywhere else. These books are read aloud, and they are shared with assistive technology more often than the category average — by blind parents reading to sighted children, and by sighted parents reading to blind children.
Write what a sighted reader gets from the picture, not what the file is. "Illustration, chapter four" tells nobody anything. If the picture carries something the text never states — the dog is hiding under the table, the bear is wearing the missing hat — the alt text carries it too, or the listening child misses the story. Accessible ebooks, and why they are now everyone's problem covers the rest of the obligation.
In the Interior Formatter. It handles the illustrated chapter book directly: inline images, full-page plates, bleed images and two-page spreads, each image checked against the size it will print at, and alt text carried through into an EPUB 3 that validates with zero errors and zero warnings. Start your ebook → · about the Interior Formatter
Dark mode, and the glowing rectangle
Most reading apps offer a dark theme, and a lot of reading happens at bedtime. An illustration drawn on a white background becomes a lit panel in the middle of a dark page — the one bright object on the screen, at the moment a reader least wants one.
A transparent background avoids most of it: the page color shows through and the art sits on whatever the reader chose. That works best for line drawings and spot art with no painted edge. Watch the opposite failure while you are there, since black line art on transparency can vanish into a dark page. How reading systems treat images in a dark theme varies, so check the file in dark mode on more than one rather than assuming a rule.
File size grows faster than you expect
Full-page color art is the whole of the file. A text novel is a few hundred kilobytes; a book with dozens of full-page color illustrations runs into tens of megabytes. Stores treat size differently, and some meter it in ways that reach your earnings, so know the number before you upload. Why your ebook is enormous, and what to do has the arithmetic.
What our tools do here, honestly
The Interior Formatter serves the illustrated chapter book and the illustrated middle grade novel well: a .docx of chapters, images placed inline or as full-page plates, bleed and two-page spreads for the print edition, alt text carried into the EPUB, and a final page count that flows to the Cover Maker. It also exports the ebook cover at 1600 × 2560, which is not your print front — see Ebook cover size, and why it is not your print front.
A picture book with the words inside the art is a different job, and a fixed-layout one. The print half of that book is covered in Children's book interiors, and its color pages are the most expensive decision in the whole edition — see Using color inside the pages.
A book the child works in rather than reads has no useful digital edition at all: whatever a coloring page is, it is not a file. Coloring books is the print-only case.
Make your ebook
The tools are free to use: bring your manuscript once and get both a print PDF and an EPUB out of the same source, so the two editions cannot drift apart. You only pay when you want the files without the preview watermark.
Next: Fixed layout: when the page is the design · More: Children's book interiors · Putting images inside a book · Accessible ebooks, and why they are now everyone's problem