10.5 font is not too small for a resume. 10.5 font is the smallest recommended size you can use on a resume that is still readable. Try a 10.5-point font if you have a lot of relevant experience, achievements, skills, and certifications to put on your resume and need to keep it to one or two pages.
Be aware that some fonts look smaller than others. If you want to use any of the following fonts on your resume, use a font size bigger than 10.5 points:
- Gill Sans