Cidfont F1 F2 F3 F4 F5 F6 Full ((free)) -

Understanding "CIDFont F1 F2 F3 F4 F5 F6 Full": A Guide to PDF Font Issues

Cons / trade-offs

• Larger file size: Full embedding of CIDFonts (especially CJK) can add many megabytes.
• Distribution/licensing: Some fonts prohibit full embedding; license checks or font subsetting may be required.
• Performance: Slower download/opening on constrained devices due to larger PDF size.
• Redundancy: Multiple full fonts may duplicate glyphs across font files, increasing size.

1. CidFont F1: This font is also known as "GBK" or " Chinese Character Set". It contains approximately 26,000 characters, mostly used for Simplified Chinese.
2. CidFont F2: This font is similar to F1 but contains a different set of characters, also for Simplified Chinese.
3. CidFont F3: This font is used for Traditional Chinese, with a character set similar to Big5.
4. CidFont F4: This font is used for Japanese characters, with a set of approximately 6,800 characters.
5. CidFont F5: This font is used for Korean characters, with a set of approximately 10,000 characters.
6. CidFont F6: This font is used for a mix of CJK characters, including some non-CJK glyphs.

3. Ghostscript and Substitution

In Linux environments using Ghostscript, a common warning is: Substituting font CIDFont=F1 for ... This means the system could not find the font referenced by the F1 identifier and is falling back to a default (often Courier or a generic CIDFont). cidfont f1 f2 f3 f4 f5 f6 full

Technical Comparison Table: F1–F6 at a Glance

| Type | Registry-Ordering | Primary Script | Base Standard | Typical Use Case | |------|------------------|----------------|---------------|------------------| | F1 | Adobe-Japan1 | Japanese (Kanji + Kana) | JIS X 0208 | Magazines, books, web | | F2 | Adobe-GB1 | Simplified Chinese | GB 2312 | Mainland China publishing | | F3 | Adobe-CNS1 | Traditional Chinese | Big Five / CNS 11643 | Taiwan, Hong Kong | | F4 | Adobe-Korea1 | Korean (Hangul + Hanja) | KS X 1001 | Newspapers, official docs | | F5 | Adobe-KR (rare) | Korean (legacy) | Older KS standards | Legacy systems (deprecated) | | F6 | Adobe-Japan2 | Japanese (supplementary) | JIS X 0212 | Academic, historical texts | Understanding "CIDFont F1 F2 F3 F4 F5 F6

Last updated: October 2025. For questions about specific PDFs, use pdffonts -subst and inspect the font objects directly. Never trust a display name alone. Larger file size: Full embedding of CIDFonts (especially