Free Tools for Car Builders
Calculate costs, analyze links, and plan your build. No account required.
Build Cost Calculator
Calculate your total build cost and generate a shareable breakdown.
- Add unlimited parts by category
- Visual cost breakdown chart
- Generate shareable image
Tire Size Calculator
Compare two tire sizes side-by-side. See diameter, circumference, and speedometer error.
- Side-by-side tire comparison
- Speedometer error calculation
- Clearance change estimates
Bolt Pattern Checker
Look up your bolt pattern and find compatible wheels for your vehicle.
- Vehicle bolt pattern database
- Compatible wheel lookup
- Hub bore reference
OBD2 Code Lookup
Search 150+ OBD-II diagnostic trouble codes with causes and fixes.
- 150+ diagnostic codes
- Causes and fix suggestions
- Severity color coding
Oil Capacity Guide
Find oil capacity, viscosity, and filter part number for your vehicle.
- 60+ vehicle database
- Oil capacity & viscosity
- Filter part numbers
HP & Torque Calculator
Convert between horsepower, torque, and RPM using the standard formula.
- Solve for HP, torque, or RPM
- Common engine specs table
- Real-time calculation
Gear Ratio Calculator
Calculate speed at redline per gear and RPM at any target speed.
- Speed at redline per gear
- RPM at target speed
- Visual speed bar chart
Compression Ratio Calculator
Calculate engine compression ratio from bore, stroke, chamber, and gasket specs.
- Full engine geometry inputs
- Metric/imperial toggle
- Octane recommendations
Fuel Injector Calculator
Size your fuel injectors based on target horsepower, fuel type, and duty cycle.
- Injector size recommendation
- Duty cycle calculator
- E85 & gasoline support
0-60 MPH Estimator
Estimate 0-60 time, quarter mile ET, and trap speed from power-to-weight.
- 0-60 & quarter mile estimates
- Famous car comparison
- Drivetrain & tire factors
Fuel Cost Calculator
Compare fuel costs between vehicles and calculate commute expenses.
- Two-vehicle comparison
- Tank range calculator
- Commute cost estimator
Engine Displacement Calculator
Calculate engine displacement from bore, stroke, and cylinder count with overbore support.
- Metric & imperial units
- Overbore calculator
- Common engine quick-load
Tire Pressure Calculator
Calculate how temperature changes affect tire pressure with track day cold pressure tool.
- Temperature correction
- Track day cold pressure
- Visual pressure indicator
Turbo Sizing Guide
Find the right turbo for your power goals with intercooler and wastegate recommendations.
- 19-turbo database
- Intercooler & wastegate sizing
- Full turbo comparison table
Brake Size Guide
Look up OEM brake specs, check wheel fitment, and explore big brake kit upgrades.
- OEM rotor & caliper specs
- Minimum wheel size calculator
- BBK compatibility guide
Coolant Mix Calculator
Calculate the right antifreeze ratio for your climate with freeze and boil protection.
- Freeze & boil protection
- Drain & fill calculator
- Coolant type reference
Affiliate Earnings Calculator
Estimate how much you could earn from your build recommendations.
- Estimate monthly earnings
- Compare affiliate programs
Bio Link Analyzer
Analyze your current Linktree and find monetization gaps.
- Analyze any bio link
- Get optimization score
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