Estimate added poke and remaining stud engagement for slip-on or bolt-on spacers. Practice minimum ≈ 1× stud diameter — free, private, instant, in-browser.
Measured thread engagement before the spacer. Leave blank if unknown.
Used for the 1× diameter practice minimum on slip-on spacers.
1"
Poke added
0.5"
Remaining engagement
0.5"
Practice minimum
Yes
Meets practice min
Slip-on spacers consume stud engagement equal to their thickness. Confirm thread engagement after installation.
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Your files never leave this device
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Close the tab and the input is gone
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Enter spacer thickness (about 0.05–4 inches). Added poke toward the fender is that thickness. This is not a solver for “what thickness gives me ET20” — you already chose a spacer (or a stack) and want to know how far the wheel moves out and whether the studs still have enough thread.
On slip-on (slip-over-stud) spacers, remaining engagement is current engagement minus thickness. Shop practice here is at least about 1× stud diameter remaining. If you enter optional engagement and stud diameter, the tool says whether that practice minimum is met. Too little thread is a safety issue, not a stance preference.
Bolt-on (hub-centric, their own studs) spacers do not shorten the OEM studs: the wheel nuts clamp the spacer’s studs instead. Poke is still the spacer thickness. You still need the correct bolt pattern, and you must torque the spacer to the hub and the wheel to the spacer as the maker specifies.
No account and no upload. Thickness and engagement stay in the tab. Close the page and they are gone. This does not check fender lip, caliper, or hub-centric fit of the spacer itself — mock up on the car after the thread math looks sane.
Slip-on slides over the factory studs. Bolt-on bolts to the hub and provides new studs for the wheel.
Poke added equals this thickness. Convert millimetres if your listing is metric (25.4 mm = 1").
Engagement is how much stud currently sticks through the wheel or hub. Remaining = engagement − thickness. Practice minimum ≈ one stud diameter.
If remaining thread is short, choose a thinner spacer, longer studs, or a bolt-on design. Do not run a slip-on on two threads.
Straight answers on privacy, limits, and how the workspace behaves.
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