NEW TO WOF TYRE RULES?
Read our complete guide covering tread depth, same-axle rules, common fails & more
NZ WOF Tyre Compliance Checker
Check if your tyres meet New Zealand WOF requirements. Our free tool verifies same-axle compatibility and the 5% diameter rule — plus shows speedometer error and LVV certification guidance.
What This Tool Checks
- Same-Axle Rules: Size, construction, pattern type, and load index matching
- 5% Diameter Rule: Compare your tyres to OEM spec (enter your vehicle or manually)
- Speedometer Error: See how larger/smaller tyres affect your speedo reading
- Tread Depth: Warns if below 1.5mm WOF minimum
NZ WOF Tyre Rules Summary
Tyres on the same axle must match in size, construction (radial/bias), and pattern type (symmetrical/asymmetrical/directional). Overall diameter must be within ±5% of OEM without LVV certification. Minimum tread depth is 1.5mm across the full width.
🔧 NZ WOF TYRE COMPLIANCE CHECKER
Drag tyres to swap positions • Click to edit • Instant compatibility results
💡 Watch: Fix Incompatible Tyres
Mismatched pattern types (SYM vs ASY) on the same axle fail WOF. Drag to swap and fix it instantly.
Search our vehicle database for your factory tyre size.
📊 52,000+ vehicles in database. Can't find yours? Try "Enter Size" and check your door placard for the OEM tyre size.
Enter your factory tyre size from the door jamb placard or owner's manual.
💡 Where to find it: Driver's door frame, fuel flap, glovebox, or owner's manual.
No worries — same-axle compatibility will still be checked. The 5% diameter rule just won't be calculated.
🔢 Understanding Tyre Sizes
205/55R16 91V
Tread width in millimetres. Wider = more dry grip but higher aquaplaning risk. Narrower = better fuel economy and wet performance.
Sidewall height as a percentage of width. Low profile (35-45) = sharper handling but harsher ride. High profile (60-75) = more comfort, better pothole protection.
Wheel diameter in inches. When upsizing rims, decrease profile to maintain same overall diameter. Example: 205/55R16 → 225/45R17.
Maximum weight per tyre. 91 = 615kg. Must meet or exceed vehicle manufacturer's spec. Under-rated tyres can overheat and blow out under load.
Maximum safe speed: T=190, H=210, V=240, W=270 km/h. Higher ratings = better high-speed stability and heat dissipation.
🔄 Pattern Types — Critical for WOF
Tyres on the same axle must have matching pattern types. Mixing patterns = instant WOF fail.
Directional tyres evacuate water 12% better than symmetrical — the V-pattern channels water outward at speed. Asymmetrical tyres have 8% better cornering grip from their reinforced outer edge. Mixing these on one axle means each tyre responds differently in emergency manoeuvres, causing unpredictable handling.
⚠️ The 5% Diameter Rule
Your tyres' overall diameter must stay within ±5% of OEM specification, or you need LVV certification.
Speedo reads slower than actual — you're going faster than shown. Odometer under-records km. Good for off-road clearance.
Speedo reads faster than actual — you're going slower than shown. Odometer over-records km. Reduced ground clearance.
📏 Tread Depth
NZ legal minimum is 1.5mm across the central 75% of the tread. Winter tyres require 4mm.
| Speed | New (8mm) | Worn (1.6mm) | Grip Loss |
|---|---|---|---|
| 50 km/h | μ = 0.55 | μ = 0.40 | −27% |
| 90 km/h | μ = 0.30 | μ = 0.10 | −67% |
| 130 km/h | μ = 0.20 | μ = 0.10 | −50% |
💡 Real-world impact: At highway speed (100 km/h) with worn tyres in rain, braking distance nearly doubles compared to new tyres. That's the difference between stopping in time and a collision.
🛞 Build Your Tyre Setup
Click slots to add tyres • Drag to swap positions
📋 Compatibility Results
WANT TO LEARN MORE?
Our comprehensive WOF tyre guide explains all the rules in plain English
