Cid Font F1 F2 F3 F4

To peek inside the PDF structure:

mutool show document.pdf /Resources/Font

Overall Verdict:
This is not a specific font name but a technical reference pattern seen inside PDF files, related to how CID-keyed fonts are organized. For a typical user, it means nothing; for a developer or forensic analyst, it indicates a structured but generic font subset.

List all fonts in a PDF, showing if they are CID and their internal names: cid font f1 f2 f3 f4

pdffonts document.pdf

Output example:

name              type         encoding     emb sub uni object ID
----------------- ------------ ------------ --- --- --- ---------
F1                CID Type0    Identity-H   yes yes yes  7 0
F2                CID Type2    Identity-V   yes yes yes 10 0

You don't have to guess. Here is how to map F1 to the real font name: To peek inside the PDF structure: mutool show document

In Adobe Acrobat Pro:

Using Command Line (pdffonts - Linux/macOS): Overall Verdict: This is not a specific font

pdffonts document.pdf

Output:

name        type         encoding     emb sub uni object ID
----------- ------------ ------------ --- --- --- ---------
F1          CID Type 0   Identity-H   yes yes yes  12  0
F2          CID Type 2   UniJIS-UCS2-H yes yes yes  14  0

This shows F1 is an embedded, subset PostScript CID font.

| Problem | Likely Cause | Solution | | :--- | :--- | :--- | | Text shows as random dots/boxes | Printer F1 font lacks a required CID | Embed the full CID font in the PDF (do not rely on printer fonts). | | "Undefined CID" error | F2 font (Chinese) is being used for Korean text (F4) | Correct the CMap in the source document (e.g., InDesign or Acrobat). | | Slow printing | Printer is swapping between F1, F2, F3, F4 on every page | Optimize PDF: embed one CID font subset instead of switching encodings. |