Sizes (French, Fr) & Typical Uses
Foley catheters are measured in French (Fr) sizes, which correspond to the outer diameter of the catheter. Common sizes:
| Size (Fr) |
Balloon Capacity |
Typical Use / Patient Group |
| 6–8 Fr |
3 mL |
Neonates, small infants |
| 8–10 Fr |
3–5 mL |
Pediatrics |
| 12–14 Fr |
5–10 mL |
Adult females, average adult use |
| 16–18 Fr |
10 mL |
Adult males, thicker urine drainage |
| 20–22 Fr |
10–30 mL |
Post-surgery, trauma, heavy drainage |
| 24–28 Fr |
30 mL |
Surgical or specialized urology cases |