For resumes, a font size of 10 to 12 pt. (depending on the particular font, but no smaller than that) is standard. Larger sizes are acceptable for headings or subheadings. Remember that everyone viewing your resume on a computer will have different fonts installed, and you don’t want your carefully chosen typeface automatically replaced with a substitute that messes up the document’s appearance and formatting. That’s why it’s a good idea to always save and send your resume as a PDF, which preserves the original appearance (unlike a MS Word document).