Are TireCalculatorPro's tools free to use?

Yes — every calculator is free, with no signup, no account, and no paywall. Results run instantly in your browser.

How many tire calculators does this site have?

80+ free calculators across 4 categories, covering tire size, pressure conversion, DOT date decoding, load index, speed ratings, and vehicle-specific fitment.

How accurate are the tire calculators?

These calculators are built on published tire industry standards (ISO/ETRTO fitment ranges, DOT date coding, metric sidewall math) for estimation and reference. For safety-critical decisions — load ratings, speed ratings, tire age — confirm the number against your tire's sidewall or vehicle owner's manual.

What is the AI Insight feature?

Some calculators include an optional "Get AI Insight" button that sends your inputs to a language model for a plain-language read on the result. It's generated on request, never automatically, and labeled as AI-generated wherever it appears.

Which vehicles have dedicated tire size calculators?

Toyota Tacoma, Ford F-150, Jeep, BMW, Audi, Lexus, Miata, Subaru, and Tesla each have a dedicated calculator pre-loaded with OEM tire sizes by generation and trim.

Pro Tire Calculators with AI Insight

Compare tire sizes, decode DOT codes, convert pressure, and check load index and speed ratings — get an instant, AI-backed answer with no signup required.

Explore All Calculators

Tire Size Tire Fit Tire Rating Vehicles

Tire Size Calculators

Free tire size calculators — compare sizes, convert measurements, calculate diameter, pressure, volume, speedometer error, and more.

Tire Size Comparison Calculator

Compare two tire sizes side by side — diameter difference, speedometer error, and fitment compatibility.

Tire Size Converter

Convert between metric (225/45R17) and standard inch tire sizes instantly.

Tire Diameter Calculator

Calculate the overall diameter of any tire from its metric sidewall code.

Gear Ratio & RPM Calculator

Calculate how a tire size change shifts your effective gear ratio and RPM at speed.

Tire Size Difference Calculator

Find the diameter, height, and width difference between any two tire sizes.

Rim Width Chart by Tire Size

Look up the recommended rim width range for any tire width from 155mm to 355mm.

Speedometer Error Calculator

Calculate exactly how much your speedometer reads fast or slow after a tire size change.

Tire Size by VIN Lookup

Look up the OEM tire size for any vehicle using its 17-character VIN number.

Wheel Offset & Backspacing Calculator

Calculate wheel offset and backspacing — and see how changes affect track width.

AWD Tire Size Tolerance Calculator

Check if your tire size difference is within safe limits for your AWD system.

Plus-Size & Winter Downsize Calculator

Calculate plus-one or plus-two upgrades, or find the right downsize for winter wheels.

Tire Pressure After Size Change

Find the correct inflation pressure after switching to a different tire size.

Tire Aspect Ratio Calculator

Calculate sidewall height in mm from any tire's aspect ratio — and compare across series.

Tire Sidewall Height Calculator

Calculate exact sidewall height in mm for any tire size — e.g. 225/45R17 = 101mm.

Tire Height Calculator

Calculate total tire height in inches or mm, compare two sizes, or find all metric sizes matching a target height.

Tire Diameter & Gear Ratio Calculator

See how changing tire diameter shifts your effective axle ratio and top speed.

Tire Diameter to RPM Calculator

Calculate engine RPM at any road speed for a given tire diameter and gear ratio.

Tire Diameter Chart

Reference chart of overall diameters for 200+ common tire sizes in mm and inches.

PSI to kPa Converter

Convert tire pressure from PSI to kilopascals (kPa) — with pre-computed common values.

Bar to PSI Converter

Convert bar to PSI for European tire pressure gauges and placards.

Tire Pressure by Vehicle

Find the manufacturer-recommended tire pressure for 200+ vehicles by make and model.

Cold Weather Pressure Drop Calculator

Calculate how much tire pressure drops per degree of temperature fall.

Tire Pressure Chart by Tire Size

Load Range Inflation Guide

Correct inflation pressure for each tire load range — C, D, E, F, and G.

Tire Air Volume Calculator

Calculate air volume inside any tire in litres, gallons, and cubic inches.

All Tire Size Calculators

Tire Fit Calculators

Check if a tire fits your rim, find rim width, calculate stretch, contact patch, rolling radius, alignment, and more.

Will This Tire Fit My Rim?

Enter any tire size and rim width — get an instant compatibility verdict with rim range.

Rim Width Calculator for Any Tire

Rim Width for 225mm Tires

Rim Width for 245mm Tires

Rim Width for 255mm Tires

Rim Width for 265mm Tires

Rim Width for 275mm Tires

Rim Width for 305mm Tires

Staggered Tire Calculator

Calculate stagger safety for AWD — diameter variance percentage and transfer case risk verdict.

Tire Contact Patch Calculator

Calculate tire contact patch area in cm² at any inflation pressure and corner load.

Tire Proration & Warranty Calculator

Calculate prorated tire warranty credit based on remaining tread depth vs original.

Spare Tire Compatibility Calculator

Check if a spare or donut tire is compatible with your vehicle — diameter match and AWD rules.

Visual Tire Size Comparison

Side-by-side visual comparison of two tire sizes at true relative scale — see the difference instantly.

Tire Revolutions Per Mile Calculator

Calculate revolutions per mile and rolling circumference for any tire size.

Tire Tread Depth Calculator

Calculate remaining tire life percentage from tread depth in mm or 32nds of an inch.

Rolling Radius Calculator

Calculate static and dynamic (loaded) rolling radius for any tire size.

Scrub Radius Calculator

Calculate scrub radius from wheel offset, kingpin inclination, and tire contact point.

Caster, Camber & Toe Angle Calculator

Calculate caster, camber, and toe angles — convert degrees to millimetres for alignment.

Tire Rolling Resistance Calculator

Calculate rolling resistance force and estimate fuel economy impact for any tire.

Static Loaded Radius Calculator

Calculate static loaded radius for vehicle dynamics, ABS calibration, and towing.

Tire Rotation Pattern Guide

Find the correct tire rotation pattern for FWD, RWD, AWD, and directional tires.

Rim Size Calculator

Calculate the correct rim diameter and width for any tire size.

Rim Size Converter

Convert rim sizes between metric and imperial — and between bolt pattern formats.

Rim Size by VIN Lookup

Look up the factory rim size for any vehicle using its 17-character VIN.

Rim Size Comparison Calculator

Compare two rim sizes — diameter and width difference and fitment impact.

Tire Stretch Calculator

Calculate stretch percentage, adjusted sidewall height, and safety stage for any tire-rim combo.

All Tire Fit Calculators

Tire Rating Calculators

Decode UTQG ratings, DOT date and plant codes, look up speed and load index, compare treadwear ratings.

UTQG Tire Rating Decoder

Decode any UTQG code — treadwear number with lifespan estimate, traction, temperature.

Tire Treadwear Rating Comparison

Compare two UTQG treadwear ratings to estimate relative lifespan difference.

Tire Age from DOT Code Calculator

Enter the 4-digit DOT date code from your sidewall to find your tire's exact age.

DOT Year Code Reference Chart

Complete chart of all DOT year codes from 2000–2030 with week-to-date lookup.

Full Tire DOT Code Decoder

Decode every section of the DOT code — plant ID, tire size code, and manufacture date.

Tire Plant Code Lookup

Look up any 2-character DOT plant code to find the tire's manufacturing location.

Pre-2000 Tire DOT Code Decoder

Decode older 3-digit DOT date codes from tires manufactured before 2000.

Tire Sidewall Code Decoder

Decode the full tire sidewall code — width, aspect ratio, rim, load index, and speed rating.

Tire Speed Rating Lookup

Look up any speed rating letter (H, V, W, Y) — max speed in mph and km/h.

Tire Load Index Lookup

Look up any load index number (71–130) — maximum load capacity in kg and lbs.

Tire Load Range Chart

Full load range chart (C through G) with max load, ply rating, and inflation data.

Vehicle Tire Load Capacity Calculator

Calculate total load capacity for a vehicle based on tire load index and count.

Tire Load Rating for Towing

Find the minimum load index required to safely tow your trailer weight.

Tire Load vs Inflation Pressure Table

Lookup table showing how load capacity changes with inflation pressure for LT tires.

XL vs SL Tire Load Index

Compare XL (Extra Load) and SL (Standard Load) index values side by side.

Tire Speed & Load Index Lookup

Look up speed rating and load index together for any tire sidewall code.

All Tire Rating Calculators

Vehicles Calculators

OEM fitment guides and tire size calculators for Toyota Tacoma, F-150, Jeep, BMW, Audi, Lexus, Miata, Subaru, Tesla, and specialty vehicles — all generations covered.

Toyota Tacoma Tire Size Calculator

All-generation Tacoma tire tool — OEM sizes for G1–G4, compare stock vs upgrade, speedometer correction, and lift kit fitment guide.

F-150 Tire Size Calculator

Ford F-150 tire calculator covering all trims (XLT, Lariat, Raptor, Lightning) — OEM sizes, speedo correction, and lift guide.

Jeep Tire Size Calculator

Jeep Wrangler and Gladiator tire calculator — all generations, crawl ratio, gear ratio, and lift fitment.

BMW Tire Calculator

BMW tire size calculator for all series — OEM fitment, staggered setup check, and size comparison.

Audi Tire Size Calculator

Audi tire calculator covering A3 through Q8 — OEM sizes, staggered fitment check, and speedometer correction.

Lexus Tire Size Calculator

Lexus tire size calculator — IS, ES, RX, GX, and LX models with OEM fitment, comparison, and generation specs.