California C-50 License Practice Exam 2026 – Comprehensive Test Prep

In reinforcing bar sizing, the size number corresponds to the approximate diameter in inches, using eighths of an inch. Multiply the size by 1/8 inch to get the diameter. So a #5 bar is about 5/8 inch in diameter (0.625"). Deformed just refers to the ribbed surface for bonding with concrete, not to the diameter. For reference, #3 is about 3/8", #4 is about 1/2", #6 is about 3/4", and #8 is about 1 inch. Therefore, the approximate diameter of a #5 deformed bar is 5/8 inch.