Automotive tools & calculators
Everything on this page is free, works on your phone and needs no account. Pick a tool and start immediately.
Diagnostics
10Interactive Car Diagnostic
Answer guided questions to narrow down why your car is behaving badly.
☆Air Conditioning Diagnostic
Step-by-step guide to find out why the AC is not cooling.
☆OBD-II Code Lookup
Search thousands of diagnostic trouble codes with causes and fixes.
☆OBD-II Live Scanner
Live RPM, speed, coolant and battery over Bluetooth with a BLE ELM327 adapter.
☆Photo Diagnostic Assistant
Photograph a tire, pad, disc or leak and follow an inspection checklist.
☆Sound Diagnostic Assistant
Record an engine noise and match it to likely causes.
☆Live OBD PID Data
Real-time engine data with charts — RPM, speed, coolant, MAF, load and battery analysis.
☆OBD Protocol Compatibility
Find which OBD protocol your vehicle uses — CAN, KWP2000, J1850 and more.
☆VIN Decoder & Vehicle Profile
Decode any VIN into make, model, year, engine, plant and specs — then jump straight to the right tools for that car.
☆Safety Recall Check
Search official safety recalls for a car by make, model and year — or by VIN — and see the fault, the risk and the free remedy.
☆Electrical
3Battery Calculator
Estimate battery health from open-circuit voltage and estimate runtime.
☆Charging System Check
Analyze alternator and charging voltage with the engine off, idling and loaded.
☆Wire Gauge & Voltage Drop Calculator
Pick the right cable section (mm² / AWG) for a run from current, length and acceptable voltage drop — with ampacity and fuse sizing.
☆Engine
8Oil Change Calculator
Oil quantity, service interval, filter and full service checklist.
☆Torque Specs Lookup
Search verified tightening torque values for common components.
☆Spark Plug Calculator
Replacement interval, cost and a quick misfire symptom assistant.
☆Cooling System & Coolant
Overheating diagnostic tree and coolant mix calculator.
☆Engine Compression Calculator
Theoretical compression ratio from bore, stroke and chamber volume.
☆Engine Builder Calculator
Displacement, piston speed and power estimates from bore and stroke.
☆Power & Torque Converter
Convert kW ↔ hp, Nm ↔ lb-ft and derive torque from power at RPM.
☆Oil Change Specs
Exact oil quantity, viscosity and filter for your car model and engine.
☆Brakes & Tires
6Tire Calculator
Decode tire sizes and compare two sets with speedometer impact.
☆Wheel Diameter Calculator
Total diameter, circumference and distance per revolution.
☆Wheel Offset & Fitment
Convert offset and backspace, and see how a new wheel changes inner clearance and poke.
☆Tire Pressure Converter
Convert PSI, bar, kPa and kg/cm², and adjust the target for temperature and altitude.
☆Tire Age / DOT Decoder
Decode the DOT date code to find the manufacturing week, year and true age of a tire.
☆Brake Calculator
Disc thickness, pad wear alerts and replacement cost estimate.
☆Fuel & Economy
2Fuel Consumption Calculator
L/100 km, MPG, trip cost with fuel price and tolls.
☆Fuel Log & Consumption Tracker
Track every fill-up and get your real L/100 km, cost per km, average price and CO₂ — stored privately on your device.
☆Transmission
2Gearbox & RPM Calculator
RPM ↔ speed, gear ratio and final drive impact on your car.
☆Clutch & Gearbox Estimator
Estimate clutch wear from mileage and symptoms, plan the gearbox oil service (MTF/ATF/CVT/DCT) and price the replacement.
☆Garage & Billing
13Garage Quote & Invoice Generator
Build professional estimates and invoices, then export as PDF.
☆Repair Cost Calculator
Real cost, margin and client price for any repair job.
☆Parts Margin Calculator
Set different margins for retail and professional customers.
☆Labor Cost Calculator
Time × hourly rate, plus parts and extras for the full bill.
☆Customer Manager
Client cards, linked vehicles and service history — stored only on your device.
☆Digital Service Book
VIN, mileage and full maintenance history per vehicle.
☆Service Reminders
Push notifications when an oil change or service comes due.
☆Vehicle Dashboard
A live status board per vehicle, computed from your service book.
☆Garage Dashboard
Revenue, accepted quotes, most profitable work and clients at a glance.
☆Parts Inventory
Track part stock with low-stock alerts and stock value.
☆Voice Assistant
“Create a quote for brake pads” — spoken commands become actions.
☆Photo → Quote
Photo of the car → confirm works → parts + labor → quote PDF.
☆Diagnostic Report Generator
Build a printable diagnostic report from a code or symptom with findings and checks.
☆Learn
6Maintenance Checklist
Interactive 10,000 km service checklist you can tick on your phone.
☆Mechanic Quiz
Test your automotive knowledge and learn with explanations.
☆Which Tool Do I Need?
Pick an operation and get the exact tools, steps and safety warnings.
☆Mechanic Training
6 levels of interactive lessons and quizzes — from fundamentals to advanced.
☆AI Mechanic Assistant
13 free AI tools: mechanic chat, OBD explainer, photo inspection, voice commands, trip planning and more.
☆Car Programming & Tuning
ECU tuning, module coding, keys/immobilizer, gains calculator, coding logbook and tuning glossary.
☆Sign in to use the planner
Keep every car's schedule, service history, mileage and maintenance costs in one place — and be told before a deadline is missed.
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