Free Automotive Tools
Interactive calculators, fitment tools, and printable checklists. Built for mechanics, DIYers, and anyone who'd rather check the math once than redo a bad install. No signup, no ads, no analytics — every tool runs on your device.
Bar to PSI Converter
Convert tire pressure between bar, PSI, and kPa live. Door-jamb sticker decoder, common car/truck pressures, severity badge. NIST-exact factor. Reviewed by Mike Reeves, ASE Master Tech.
Open toolWheel Offset Calculator + Visualizer
Compare stock vs new wheel setup with poke/tuck delta, backspacing, plain-English fitment severity, and SVG fender visualizer. Spacer-aware. Reviewed by Mike Reeves, ASE Master Tech.
Open toolTire Height & Diameter Calculator
Compare any two tire sizes — diameter delta, speedometer error %, revs per mile, lift estimate with vehicle presets, and a branded PDF spec sheet. Plus-size helper built in. Reviewed by Mike Reeves, ASE Master Tech.
Open toolTire Ply Rating + Load Index Chart
Look up any sidewall code or load index — Load Range letter, ply equivalent, max PSI, and capacity in lb/kg. Interactive filter by passenger / LT / trailer / heavy-duty. Live load-index slider, branded PDF, embeddable widget. Reviewed by Mike Reeves, ASE Master Tech.
Open toolBolt & Lug-Nut Torque Calculator
Two modes in one tool: bolt torque (T = K × D × F) for any size + grade + lubrication, plus a lug-nut chart by stud size. Live ft-lb / Nm / in-lb display, star-pattern reminder. Reviewed by Mike Reeves, ASE Master Tech.
Open toolFt-Lbs to Nm Torque Converter
Convert torque between ft-lb, N·m, and in-lb live in three linked fields. Mechanic-flavored: lug-nut + spark-plug + oil-drain presets, wrench-class chip, branded PDF. NIST-exact factor. Reviewed by Mike Reeves, ASE Master Tech.
Open toolJump Start Order — Animated Diagram
Step-by-step animated jumper-cable connection diagram with 5 scenarios (car-to-car, jump pack, hybrid, EV, motorcycle), 'why this order' callouts on every step, and a printable wallet card. Reviewed by Mike Reeves, ASE Master Tech.
Open toolUsed Car Inspection Checklist
61 ASE-shop inspection points across 9 sections — interactive on your phone in the seller's driveway. Live deal-score, walk-away alerts for title/frame/engine red flags, and a one-page PDF report with your vehicle data. Reviewed by Mike Reeves, ASE Master Tech.
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