Puncture location and damage severity can help determine whether to get a tire repaired or replaced. For example, a simple repair may do the trick if you have a tire that's been punctured in the tread area and doesn't measure more than a quarter of an inch (6 mm) in diameter.
Even if a tire has two punctures, getting it repaired might still be an option if they are at least 16 inches apart and the maximum number of repairs over time isn't more than two. If there are more than that, however, you should consider replacing them.
Punctured tires will likely need replacement if:
The hole is over a quarter of an inch in diameter.
The sidewall or shoulder is punctured.
Multiple punctures are less than 16 inches apart.