Skip to content
EPUBCheck · XHTML content documents

HTM-004

Updated:

EPUBCheck HTM-004 is an error message: “Irregular DOCTYPE: found "…", expected "…".” A document has a DOCTYPE other than the one expected for its EPUB version; EPUBCheck shows both.

The official message

Irregular DOCTYPE: found "%1$s", expected "%2$s".

Default severity
Error. The EPUB breaks a rule of the specification and is invalid. Stores and Send to Kindle may reject it, and EPUBCheck exits with status 1.
EPUBCheck version
5.4.0

%1$s, %2$s… are filled in with the file, value or element EPUBCheck found.

Typical causes

How to fix it

  • For EPUB 3 XHTML, use <!DOCTYPE html>.

Terms used here

Other HTM messages

  • HTM-003 External entities are not allowed in EPUB v3 documents. External entity declaration found: ….
  • HTM-009 The DOCTYPE provided is obsolete or irregular and can be removed.
  • HTM-010 Namespace "…" is unusual for the prefix "epub".
  • HTM-011 Entity is undeclared.
  • HTM-025 Non-registered URI scheme type found in href.
  • HTM-045 Encountered empty href.

Message text and severity from EPUBCheck 5.4.0 (W3C, BSD-3-Clause). Explanation by EPUBLab.

FAQ

What does EPUBCheck HTM-004 mean?

EPUBCheck HTM-004 is an error message: “Irregular DOCTYPE: found "…", expected "…".” A document has a DOCTYPE other than the one expected for its EPUB version; EPUBCheck shows both.

Is HTM-004 an error?

HTM-004 is reported as error by default. The EPUB breaks a rule of the specification and is invalid. Stores and Send to Kindle may reject it, and EPUBCheck exits with status 1.