Cf. Abbreviation
Cf. is a comparison signal in formal writing. Its core function should be distinguished from a generic “see” reference, and its punctuation should follow the applicable editorial style.
Use cf. when you are asking the reader to compare another source or point. Some style systems omit the period, so follow the style guide governing the document.
Key details
Important caveats
Usage Boundary
Do not automatically substitute cf. for “see”: cf. specifically signals comparison, so the intended relationship matters.
Further guidance
Form
Cambridge records both “cf.” and, in Business English material, “cf”; punctuation can therefore depend on style.
Meaning
Cf. is used in formal writing to mean that the reader should compare the cited or mentioned material.
Practical Application
Use cf. when the reader should compare the cited material with the present point; use a simple “see” reference when you only want to direct the reader elsewhere. Follow the governing style on whether the abbreviation keeps its period.
Reader Check
Is the relationship genuinely comparative, rather than merely a pointer to supporting or additional information?
Worked Example
“Cf. section 4 for a different treatment of the same term” signals comparison. “See section 4 for definitions” is clearer when no comparison is intended.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- CF — Cambridge Dictionary (opens in a new tab)Cambridge University Press · cf./cf meaning and comparison function in formal writing