Rebar Size Chart (#3–#8)
Quick reference for common rebar sizes used in slabs and structural applications.
| Bar size | Nominal diameter | Area (in²) | Typical use |
|---|---|---|---|
| #3 | 3/8" | 0.11 | Light slabs, residential crack control. |
| #4 | 1/2" | 0.20 | Common residential/commercial slab reinforcement. |
| #5 | 5/8" | 0.31 | Heavier loads; often engineered layouts. |
| #6 | 3/4" | 0.44 | Industrial/structural use; usually engineered. |
| #7 | 7/8" | 0.60 | Structural applications. |
| #8 | 1" | 0.79 | Structural applications. |
| Values shown are common references. Confirm local standards/specs for critical work. | |||
Practical note: In slabs-on-grade, reinforcement is often used for crack control and load distribution. It does not substitute for a proper base, drainage, and joint plan.