Free Online Tools & Calculators
Free online calculators and converters for tool buyers and engineers: unit converter, torque conversion, drill bit sizes, chainsaw chain guide, wire gauge, cutting speed and more.
Unit Converter
Convert between metric and imperial units used in the tool industry: length (inch/mm), weight (kg/lb), torque (Nm/ft-lb), power (kW/HP) and more. Free, instant and accurate.
→Torque Conversion Calculator
Convert torque values between Newton-meter (Nm), foot-pound (ft-lb), inch-pound (in-lb) and kilogram-force meter (kgf-m). Essential for impact wrenches, torque wrenches and fastener specs.
→Power Converter (kW/HP)
Convert power ratings between kilowatt (kW), horsepower (HP), metric horsepower (PS) and watt (W). Perfect for comparing engines, generators and power tools.
→Pressure Converter
Convert pressure values between bar, PSI, MPa, kPa and kg/cm². Essential for air compressors, pressure washers and hydraulic systems.
→Drill Bit Size Converter
Convert and compare drill bit sizes between fractional inches, wire gauge numbers, letter sizes and metric diameters. Includes a complete decimal inch and millimeter chart.
→AWG to mm² Wire Gauge Converter
Convert American Wire Gauge (AWG) to square millimeters (mm²) and diameter, with ampacity reference for common applications. Essential for extension cords and power tools.
→Cutting Speed & RPM Calculator
Calculate spindle RPM from cutting speed and workpiece diameter for drilling and milling. Includes recommended cutting speeds for common materials.
→Chainsaw Chain Guide
Learn how to identify chainsaw chain pitch (1/4", 3/8", .325", 3/8" LP), gauge and link count. Free reference chart for chainsaw chain replacement.
→Chainsaw Chain Length Calculator
Calculate chainsaw chain length from drive-link count and pitch. Enter your drive links and chain pitch to get the total chain length in inches, cm and mm.
→Bolt & Screw Size Chart
Complete bolt, screw and wrench size reference: metric and imperial thread sizes, wrench sizes, hex key sizes and torque reference for common fasteners.
→Bolt Torque Chart
Recommended tightening torque for metric coarse-thread bolts by property class (8.8, 10.9, 12.9). Free reference chart for mechanics, engineers and DIY users.
→Air Compressor Size Calculator
Select your pneumatic tools to calculate the required CFM and recommended air compressor size. Free tool sizing calculator for workshops, garages and professionals.
→Extension Cord Size Chart
Find the right extension cord gauge for your power tools. Enter the amp draw and cord length to get the recommended AWG, with a complete 18–10 AWG reference chart.
→CC to HP Converter
Convert engine displacement (cc) to horsepower (HP) and back for small engines: chainsaws, brush cutters, tillers, generators and more. Includes the typical 14–17 cc per HP range.
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