MechanixCalc

MechanixCalc is web-based machine design and verification software for mechanical engineers. Fifty modules cover gears, bearings, shafts, bolted joints, beams and columns, welds, pressure vessels, pipe flow, hydraulics, pumps and lifting gear.

Each module works through the method of the standard it names - ISO 6336 for cylindrical gears, ISO 281 for bearing life, VDI 2230 for bolted joints, DIN 743 for shaft fatigue, ASME VIII for pressure vessels, EN 1993-1-8 for welds, ASME B31.3 for pipe stress - shows the formula and a worked numeric example, and returns an honest PASS / REVIEW / FAIL verdict. Where a panel uses an accepted simplified model rather than a single citable standard, it is clearly labelled as an engineering estimate rather than claiming a standard it does not implement.

Work is saved to a project you can reopen later, and every calculation exports to a branded PDF engineering report that a reviewer or client can follow line by line, as well as Excel and CSV.

It is built for the gap between free single-answer web calculators, which give you a number you cannot defend in a design file, and heavyweight desktop packages such as KISSsoft or MITCalc, which are powerful but expensive and install-bound.

Also included: a unit converter, an engineering reference library, side-by-side comparison mode, P&ID, fluid power and electrical schematic editors, a REST API, and an Autodesk Fusion 360 add-in in invite-based early access that reads the geometry you select and returns numbers only, so your CAD model never leaves your machine.

There is a permanently free tier, a 30-minute preview of any tool with no signup, and a 14-day trial with no card required.