Fit comparison tool updates
(4 total)- 2026-04-01 — Updated title, software patch for fractional sizes.
- 2026-03-25 — Added 'Try our other tools' navigation cards.
- 2026-03-22 — Fit comparison module created.
- 2026-03-22 — Manually calibrated data of 60 running shoe models added.
Compare Fit Across Models
Your Size In ...
Fit Profile: ...
This sizing tool helps you compare the fit across 60 current running shoe models. We combined our internal standardization of footwear sizes across a dozen brands with manually calibrated data for specific shoe models. Our visual fit banner tells you whether a shoe fits true to size, loose, or tight, while our ‘fit notes’ section contains brief commentary on that specific model. If a shoe fits shorter or longer than expected, our fit notes will explain why. This is the only such online tool that lets you compare the fit and sizing across different running shoe models.
Here’s an example based on our current dataset. Using this tool, if you choose: ‘If my size in Asics Novablast 5 is US Men’s 10, then what is my size in the Asics Metaspeed Sky Tokyo? Our tool will return a US 9.5. This is because the decreased heel padding shifts the foot away from the toe-box, creating a half-size looser/longer fit. That means you would need to buy a US 9.5 in the Asics Metaspeed Sky Tokyo to get the same level of fit security as a Novablast 5 in US 10.
Our tool also accounts for variations in sizing standards across different brands. If you choose ‘If my size in Asics Novablast 5 is CM (JP) 29.5, then what is my size in adidas Boston 13? Our tool will tell you that the equivalent CM (JP) size is 30, because that’s how the adidas sizes its shoes. We have also mapped the conversion variances between US and UK sizes across major footwear brands.
The goal of this tool is not guarantee a perfect fit for your feet; the variances in foot shapes and personal fit preferences makes that extremely difficult. Instead, the goal is to remove several layers of guesswork while making traditional sizing charts a thing of the past.