EngReference
Mechanical engineering reference
Calculators and reference tables for mechanical engineering — tolerances, fasteners, stress analysis, materials, and more.
All categories
Tolerances
2/4 live tools
Calculators and reference tables for dimensional tolerances, fits, and geometric deviations.
ISO 286 — Engineering Fits
A tool for calculating shaft and hole tolerances according to ISO 286.
ISO 2768 — General Tolerances
General tolerances according to ISO 2768 standards.
Tolerance Stackup
Worst-case and statistical stackup analysis
GD&T Reference
Geometric dimensioning and tolerancing symbols
Fasteners
1/4 live tools
Calculators and reference tables for everything fastener related.
ISO 273 — Clearance Holes
Calculator tool to size clearance holes for metric fasteners according to ISO 273.
Bolt Torque & Preload
Tightening torque and clamp force for metric bolts
Thread Engagement Length
Minimum engagement for full thread strength
Bolt Pattern
Bolt circle layout and load distribution
Calculators
1/4 live tools
A collection of calculators for various engineering applications.
Shear Joint Calculator
Calculator for determining the shear capacity of mechanical joints.
Beam Deflection
Deflection and bending stress for common load cases
Torque & Shaft Stress
Torsional shear stress and power transmission
Buckling (Euler)
Critical load for slender columns
Materials
0/3 live tools
Mechanical properties and selection data for common engineering materials.
Material Properties Table
E, G, yield, UTS, density for metals and polymers
Material Selector
Filter materials by property requirements
Unit Converter
Stress, force, pressure, and length conversions
Springs
0/3 live tools
Spring rate, stress, and fatigue life for compression, extension, and torsion springs.
Compression Spring
Rate, stress, and natural frequency
Extension Spring
Rate and initial tension
Torsion Spring
Angular rate and stress
Fluid Mechanics
0/3 live tools
Pipe flow, pressure drop, and Reynolds number calculations.
Pipe Flow
Reynolds number, flow regime, friction factor
Pressure Drop
Darcy-Weisbach for pipes and fittings
Orifice Flow
Flow rate through an orifice
Values for reference only — verify against applicable design standards before use.