Upload an EPUB and the studio runs EPUBCheck on it, the same check KDP, Apple and Kobo rely on. You see every error and warning with where it is and what it means. The file is deleted as soon as the check ends.
What you need: an EPUB of up to 30 MB.
EPUB validator
Check an EPUB with EPUBCheck, the stores' own validator, and see what it finds in plain words.
On every plan, the Free plan included.
More in Free public tools
- Barcode generatorAn ISBN barcode as a print-ready PDF or SVG, free.
- Language checkerWhich stores sell ebooks and print books in a given language. Free, no account needed.
- Page count estimatorHow many pages a book will print at, from its word count, for each trim.
- Plan your bookWhat publishing your book will cost, what each sale earns in each country, and how many copies pay it back.
- Royalty calculatorWhat KDP pays you per sale in each marketplace, for print and ebooks.
- Spine and cover size calculatorThe spine width and full cover size for a KDP paperback or hardcover, from its trim, paper and pages.
See it for yourself in PenStranding: start with one book on the Free plan.
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