Approx. Abbreviation and Punctuation
Approx./approx. are documented shortened forms of approximate/approximately. This is a style-and-abbreviation question rather than a universal punctuation law.
“Approx.” is a standard written abbreviation for “approximately”; “approx” also appears in Business English. Whether to keep the period can depend on house style.
Key details
Important caveats
Style Boundary
Follow the relevant house style and keep the abbreviation consistent; spell the word out where compact notation is unnecessary.
Variant Boundary
Cambridge Business English also records “approx” and “approx.” for “approximate,” so a final period is not universal across all style systems.
Further guidance
Example
House-style contrast: a table may use “approx. 25 km,” while another style may use “approx 25 km.” In running prose, “approximately 25 km” avoids the abbreviation choice entirely.
Meaning
Cambridge records “approx.” as a written abbreviation for “approximately.”
Practical Application
Use “approx.” or “approx” only when an abbreviation is appropriate for the document. The reviewed dictionary records both shortened forms; the period is therefore a style decision rather than a universal correctness test.
Reader Check
Check the governing house style and the surrounding abbreviations. In formal prose, writing “approximately” in full may be clearer than introducing a shortened form.
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.
- Approx. — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Approx./approx as written abbreviation for approximately or approximate