How to Enter EPUB Metadata
If you have a certain library of E-Books from different sources (e.g. Baen, Gutenberg, Archive.org, Google Books) you will notice a disparaging plethora of different styles of annotating EPUB-files, sometimes blatantly wrong and in violation of the EPUB Standard itself.
So this is a Howto on how to enter these metadata correctly. I’ll mostly cover the program “ebook-meta” (part of Calibre) which is available on about every platform.
Encoding
EPUB uses UTF-8, and UTF-8 only. Still, if you don’t use things like left-and-right quotes and backquotes, you’ll make sure your tags don’t get messed up. Ideally, only use the single quote “‘”.
Vocabulary
Try to be consistent in the vocabulary for tags (genres, categories). Sadly, no vocabularies are specified by the standards right now.
Tags
- Title: This will contain the Title as it’s read. Don’t put in the author (yes, seen that). Don’t anticipate sorting by naming it “Title, The”, this is the task of the library program which sould do this. Don’t enter Series and Series Index. Don’t enter the author here.
- Title sort: You don’t need to enter that; at least ebook-meta usually sets this correctly.
- Author(s): Enter the author as named. Don’t enter the title here (also seen..), and don’t enter things like series or title after the author’s name. Don’t anticipate sorting by naming it “Name, First Name”. Enter it in the form “First Middle Last”. If the authors name is usually used with initials, use these. Don’t enter “John Ronald Reuel Tolkien”, but “J. R. R. Tolkien”. After an initial, enter a dot and a space. If there are several authors, enter all of them, when using “ebook-meta” separate them with “&”.
- Author sort: You don’t need to enter that; at least ebook-meta usually sets this correctly.
- Publisher: This is the original publisher. If you’re preparing an out-of-copyright e-book, don’t enter yourself. Also, don’t anticipate sorting but enter it as given.
- Languages: At least one language must be set, you can set several if the book is multi-lingual. The language-code is the 2-letter iso-code. Apparently it ignores localized ones such as “en-gb”.
- Published: This is the original publishing date. Not the date you’re preparing the e-book!
- Rights: Enter the year and copyright holder, if applicable, and a license if necessary. Like this: “Copyright 1954 by J. R. R. Tolkien” or “Copyright 2012 by Peter Keel, License CC-By-2.5” or “Public Domain” if the work is not protected by copyright anymore.
- Identifiers: Here go ISBN or ISSN (for magazines) or UUID. You can put in as many as ou like. “ebook-meta” allows only to set the ISBN and a BookID specifically.
- Comments: This is actually the “Description”-tag, and it’s supposed to hold the blurb which would otherwise go onto the flap or the back of a physical book. And it should not contain HTML-tags. Also, don’t make this too long.
- Series: This is a Calibre-specific tag, however it’s honored in many e-book-readers, so you really want to use this. Enter the series as spelled. Don’t take sorting into account. Don’t enter any series number.
- Series Index: Also Calibre-specific, but goes with support for the “Series”-tag. Enter a number here, corresponding to the number in the series.
- Tags: This one is really the “Subject”-tag. It contains as many tags as you wish on what the book is about. Enter the genre here as well. Enter tags separated by comma. Do NOT enter a blurb here.
- Category: This is probably the “Type” tag but support seems to be rather limited. in any way, the genre does NOT go into that, but rather things like “textbook” or “novel”.