Free section properties calculator, unit converter, volume calculator, trajectory solver, and vector tools. General-purpose calculators useful across all engineering disciplines.
Section Properties & Moment of Inertia Calculator
Calculate Ix, Iy, Sx, Sy, Zx, Zy, radius of gyration, and torsion constant for standard shapes, AISC steel database (871 shapes), and custom composite sections.
Engineering Unit Converter
Convert between 500+ engineering units across length, force, pressure, temperature, torque, flow rate, and more.
Volume Calculator
Calculate volume and surface area for 15+ geometric shapes including cylinders, cones, spheres, toroids, and frustums.
Trajectory Calculator
Projectile motion solver with air resistance. Calculates range, max height, time of flight, and plots the trajectory.
Vector Decomposition
Decompose vectors into components. Supports 2D and 3D vectors with magnitude/angle or component input, plus vector addition and dot/cross products.
Spring Calculator
Design compression, extension, and torsion springs. Calculates spring rate, deflection, solid height, and stress per Shigley/SAE J1122.
Volumetric LDR Calculator
Calculate volumetric loading-to-displacement ratio for structural applications.
Engineering Fundamentals
These calculators cover basic engineering computations that come up constantly — unit conversions, volume estimates, projectile paths, and vector math. Designed to be fast and comprehensive, covering edge cases simpler tools miss.
Reference Data
See our Unit Conversion Tables for printable reference sheets.
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