Look up ETRTO-approved minimum, measuring, and maximum rim widths for a tire section width and aspect ratio. Confirm a size before you mount — free, private.
Tire section width in millimetres (e.g. 225).
Leave blank for a width-only fallback range.
7"
Minimum rim
7.5"
Measuring rim
8.5"
Maximum rim
Exact series
Table match
Matched an ETRTO width/aspect row. Manufacturer fitment still takes priority.
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Your files never leave this device
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Enter section width (125–405 mm) and optionally aspect ratio. You get the approved rim-width band in inches: minimum, measuring (design) width, and maximum. That is the table used to judge whether an 8" wheel is in range for a 245 mm tire — not a stretch-forum guess.
When aspect is provided and the series exists in the table, you get the exact ETRTO row. If not, the tool falls back to section width so you still see a band instead of a blank. Copy tells you which path was used so you do not treat a fallback as a full-size homologation.
The measuring rim is where the tire’s published dimensions were defined. Min and max are the approved mounting range. A tire can be mounted across that range; outside it you are in stretch or stuffing territory, which the separate stretch checker is for.
No account and no upload. The band comes from the encoded ETRTO-style table, not a live manufacturer API. The tire maker’s datasheet still wins if it disagrees. Close the tab and the millimetres you typed are gone from GetUpTools. Nothing is stored on a server.
That is the 245 in 245/45R18, in 5 mm steps from 125 to 405. This is not flotation overall width in inches.
The 45 in 245/45R18. Aspect improves the chance of an exact series row; leave it off if you only know width.
Compare your wheel’s advertised width to the band. Measuring is the design rim; min/max are the approved range.
ETRTO is the usual industry table; a specific product can differ. For stretch beyond the max, use the stretch checker — this page is the approved range.
Straight answers on privacy, limits, and how the workspace behaves.
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