wheel fitment & stance calculators
Wheel & Tyre Fitment Calculators
Free tools to check if aftermarket wheels will fit your car. Calculate offset changes, visualise poke and tuck, check AWD tyre diameter differences, understand tyre stretch, and measure your PCD bolt pattern. Used by enthusiasts across the UK to avoid costly fitment mistakes.
🎯 Wheel Fitment Calculator
Compare your current wheels against new ones. See exactly how offset, width, and spacers affect where the wheel sits - will it poke, tuck, or hit the strut?
⚙️ AWD & xDrive Checker
Running different size tyres front and rear on your BMW xDrive, Audi Quattro, or Mercedes 4Matic? Check the rolling circumference difference stays under 1% to protect your transfer case.
📐 Tyre Stretch Calculator
Fitting a tyre to a wider rim than standard? Visualise how much stretch you'll get and whether it's mild, moderate, or aggressive.
📊 Camber & Poke Helper
Running negative camber? Calculate how it affects your wheel-to-arch gap and find the right spacer size to get flush fitment.
🔩 PCD & Bolt Pattern Guide
Learn how to measure your wheel's PCD (bolt pattern). Includes reference tables for 4, 5, and 6 bolt patterns with common vehicle makes.
Need help? Our AI assistant Ally can check fitment for your specific vehicle from our database of 7,500+ cars.
Need Fitment Advice?
Not sure what fits your car? Our experts will help you find the perfect setup.
Frequently Asked Questions
What does wheel offset (ET) mean?
Offset (ET from German "Einpresstiefe") is the distance in millimetres from the wheel's mounting surface to its centreline. Positive offset means the mounting surface is towards the outside of the wheel (common on modern cars). Lower offset pushes the wheel outward (more poke), higher offset tucks it inward.
How do I know if wheels will fit my car?
You need to check several things: PCD (bolt pattern) must match exactly, centre bore must be equal or larger than your hub (use spigot rings if larger), offset should be within ~15mm of stock to avoid rubbing or clearance issues, and overall diameter affects speedometer accuracy and arch clearance.
What is poke and tuck?
Poke is when the wheel/tyre extends beyond the wheel arch. Tuck is when it sits inside the arch. Most factory cars have slight tuck. Stance enthusiasts often aim for flush (level with arch) or mild poke. Excessive poke can cause MOT failures and tyre rub on steering.
Can I run different size tyres on AWD?
AWD systems like BMW xDrive, Audi Quattro, and Mercedes 4Matic require all four tyres to have similar rolling circumference (within 1-2%). Mismatched sizes cause the transfer case to work constantly, leading to premature wear or failure. Use our AWD calculator to check your setup.
What is tyre stretch and is it safe?
Tyre stretch is mounting a tyre on a rim wider than the manufacturer's recommended width. Mild stretch (up to 8mm per side) is generally considered safe for road use. Aggressive stretch reduces sidewall protection and can cause debeading under hard cornering. It's popular in stance culture for aesthetic reasons.
How do I measure PCD (bolt pattern)?
For 4 or 6 bolt patterns, measure directly across from the centre of one bolt to the centre of the opposite bolt - this is your PCD. For 5 bolt patterns, measure from one bolt to the furthest non-adjacent bolt, then multiply by 1.051 to get the PCD.
