Running shoe replacement calculator
Estimate roughly how many weeks are left before a pair reaches a mileage target you choose, based on how much you run in it. It's a planning aid — not a verdict on whether a shoe is safe to keep running in.
How this is calculated
The math is deliberately simple and transparent, so you can see exactly what it assumes:
- Mileage remaining = replacement target − current mileage.
- Estimated weeks left = mileage remaining ÷ weekly mileage for this pair.
- Approx. replacement date = today + (weeks × 7 days).
If your current mileage already meets or exceeds the target, the tool says so instead of returning a date. If you haven't entered a weekly mileage, it shows the mileage remaining but can't estimate a timeline.
Read this before trusting the date
A mileage target is a guideline, not a deadline. Two pairs with identical mileage can be in very different condition depending on your weight, stride, the surface, and the foam. The date this tool gives you is a planning estimate — it does not tell you whether a shoe is still safe to run in. Judge that from how the pair looks and feels, using the wear signs in our replacement guide, and treat the calculator as a way to plan ahead, not a diagnosis.