FB2 vs HTML
A detailed comparison of FictionBook and HTML Document — file size, quality, compatibility, and which format to choose for your workflow.
FictionBook
eBooksFictionBook (FB2) is an XML-based eBook format popular in Russia and Eastern Europe. It provides structured semantic markup for fiction and non-fiction books.
About FB2 filesHTML Document
Documents & TextHTML is the standard markup language for web pages. As a conversion target or source, it carries text content with structural and formatting information that can be extracted or repurposed.
About HTML filesStrengths Comparison
FB2 Strengths
- Pure XML — trivial to parse, search, and transform.
- Single-file ebooks with inline images.
- Excellent on low-powered e-readers.
- De-facto standard in Russian-language ebook ecosystem.
- Simple structure makes conversion to any other format straightforward.
HTML Strengths
- Universal — every browser, OS, email client, and document reader displays HTML.
- Plain text, human-readable, grep-able, and diffable in git.
- Flexible — pages render even with broken or partial markup (error-tolerant parser).
- Carries structure, styling (CSS), and behavior (JavaScript) in one file.
- Accessibility-friendly when written with semantic tags and ARIA attributes.
Limitations
FB2 Limitations
- No styling, no custom fonts, no fixed layouts.
- Minimal Western-language tooling.
- Kindle and Apple Books do not support FB2 natively.
- Non-fiction with complex typography (textbooks, cookbooks) is a poor fit.
HTML Limitations
- Error tolerance allows sloppy markup to hide real bugs.
- Rendering depends on browser engine — pixel-perfect cross-browser output is an art form.
- Security-sensitive — unsafe HTML can execute scripts or leak data (XSS vulnerabilities).
- File size for equivalent structured data is larger than JSON or XML due to tag verbosity.
- No built-in typing or schema — contract between server and client is informal.
Technical Specifications
| Specification | FB2 | HTML |
|---|---|---|
| MIME type | application/x-fictionbook+xml | text/html |
| Extensions | .fb2, .fb2.zip | .html, .htm |
| Container | Single XML file (optionally zipped) | — |
| Standard | FictionBook community spec (maintained on GitHub) | HTML Living Standard (WHATWG) |
| Encoding | UTF-8 (required) | — |
| Character encoding | — | UTF-8 (recommended) |
| Element count | — | ~110 in current spec |
Typical File Sizes
FB2
- Novel (text only) 200-800 KB
- Novel with cover image 300 KB - 1.5 MB
- Illustrated children's book 5-30 MB
HTML
- Hello-world page < 1 KB
- Blog post (rendered HTML) 5-40 KB
- Modern SPA (initial HTML shell) 50-200 KB
- Full archived web page (with inline assets) 500 KB - 10 MB
Ready to convert?
Convert between FB2 and HTML online, free, and without installing anything. Encrypted upload, automatic deletion after 2 hours.
Frequently Asked Questions
FB2 (FictionBook) is an ebook format designed for reading long-form text on dedicated e-readers, tablets, and ebook apps. It is part of the ebooks family and typically supports reflowable text, embedded images, chapter navigation, cover art, and metadata (title, author, ISBN) in a portable package.
HTML (HyperText Markup Language) is the core language of the web, created by Tim Berners-Lee in 1993. An HTML file is plain text describing structure (headings, paragraphs, links, images), optionally with styling (CSS) and interactivity (JavaScript). Every web page you visit is rendered from HTML.
Dedicated e-readers — Kindle, Kobo, Nook, Pocketbook — support the most common ebook formats. On phones, Apple Books, Google Play Books, Moon+ Reader and KOReader all handle FB2. For desktop reading, Calibre is the universal ebook viewer and library manager. Convert to EPUB or PDF for maximum compatibility.
HTML files open in every web browser by double-clicking. To edit, use any text editor (Notepad, VS Code, Sublime Text) or a visual editor (Dreamweaver, Pinegrow). Mobile browsers also render HTML files from local storage.
Upload your FB2 to KaijuConverter and pick EPUB, MOBI, PDF, AZW3, or similar targets. Our Calibre-powered pipeline preserves chapter structure, embedded images, cover art, and metadata. Conversion takes seconds for typical novels; long technical books with many images may take a little longer.
EPUB is the open ebook standard — it plays on every e-reader except older Kindles and in every major ebook app. PDF is better for fixed-layout content (textbooks, coffee-table books) and printing. Pick EPUB when the ebook is reflowable text, PDF when the layout matters more than the reading experience.