Knowledge · Rule
Font file not declared in manifest
Fonts · E-FONT
Definition
A font file exists in your EPUB but isn't listed in the manifest, so it may not load correctly.
Why
- Fonts folder copied into the zip without OPF manifest items.
- @font-face src references a file that was added later without updating the OPF.
- Wrong media-type on a font item (optional companion issue).
- Obfuscated fonts present but undeclared after a partial encryption pass.
Impact
Often a warning on KDP; still review before upload.
Platforms
| Platform | Result |
|---|---|
| KDP | Warning |
| Apple Books | Warning |
| Google Play | Warning |
| Kobo | Usually fine |
References
- EPUB manifest — font items
- Amazon Kindle font embedding notes
- Cermify Rule Set kdp-epub-2026-07
Last updated · 2026-08-03
Why we believe
Provenance is loaded from RID (same source as Rule Radar) — not a second copy.
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