Free reference tables and calculators for mechanical design and drafting — based on UNI/EN/ISO standards. Use them right in your browser, no account needed.
Metric coarse & fine, UNC, UNF, BSP and NPT — pitch, diameters and tap drill sizes for every major thread standard.
Open tool →Tolerance field and fit calculator, plus a browsable library of ISO 286-2 preferred fits.
Open tool →Worst case, RSS, MRSS and Monte Carlo on a 1D dimension chain with ISO 286 auto-fill, contribution ranking, gap histogram, clearance/interference check and a printable report.
Open tool →Dimension tables for bolts, nuts and washers, ISO standard sizes.
Open tool →Quick K-factor and precise VDI 2230 methods for bolted joints, with a live breakdown of thread vs. bearing friction.
Open tool →Pressure, force, torque, length, mass, power, energy and more, for mechanical engineering.
Open tool →Principal stresses, maximum in-plane shear and the rotated stress element, with a live interactive circle diagram.
Open tool →Triaxial stress state: three principal stresses, absolute max shear, Tresca and von Mises equivalent stress, live three-circle diagram.
Open tool →Area, centroid, moments of inertia, principal axes, section moduli and radii of gyration for 15 common sections — circle, tube, rectangle, I, T, angle, channel and more — with a live scaled drawing.
Open tool →ISO 281 rating life for deep groove ball bearings, with equivalent load, reliability factor and a live load-sensitivity chart.
Open tool →MechaHandbook puts this whole reference library in your pocket — no signal required.
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