Condom sizing is primarily determined by rather than length, as most standard condoms are 7–8 inches long and can stretch to cover most lengths.
Standard/regular-size condoms are the correct choice if 6 inches refers to your length , as they typically accommodate penises between 5 and 7 inches long. However, if 6 inches refers to your (circumference), you will likely need extra-large (XL) or XXL condoms, which are designed for girths over 5.7 or 6 inches. Quick Fit Guide what condom should i buy for 6 inches