Slide 1 of 6: Engineering calculators that earn your trust

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Accurate Results
User-Friendly
Mobile Responsive
Free Calculators

Beyond quick calcs

Professional tools for serious work

When a back-of-envelope isn't enough — CAM toolpaths, structural solvers, and seal design that ship with your Pro plan.

Pro

Browser-based CNC

CAM Studio

Import geometry, generate 2.5D and 3D toolpaths, simulate cuts, and post G-code — without leaving the browser. Tool libraries and machine profiles sync to your account.

  • 2.5D & 3D paths
  • G-code post
  • Cloud tool library
Open CAM Studio
Pro

Structural FEA in 2D

Bridge Designer

Pick a truss, arch, cable-stayed or suspension style, sketch joints and members, then run a frame finite-element solver to find axial forces, bending moments, and the governing load factor.

  • 12 bridge styles
  • Load factor check
  • Interactive canvas
Open Bridge Designer
Pro

Seal groove sizing

O-ring Calculator

Size grooves against ISO 3601 and AS568 standards, check squeeze and stretch, and validate material compatibility — the kind of seal work that usually lives in a spreadsheet tab nobody trusts.

  • ISO & AS568
  • Squeeze analysis
  • Material library
Open O-ring Calculator
Compare Pro plans

Free calculators stay free — Pro unlocks the solvers above plus PDF export and saved workspaces.

Why Choose EngiToolbox?

Designed and maintained by a single engineer — so every detail gets personal attention.

Engineering-Grade Accuracy

Every calculation is verified against engineering standards to ensure precision you can trust

Intuitive Interface

Simple, modern design that provides a seamless experience for engineers and students alike

Growing Collection

New calculators and refinements ship regularly, with every release shaped by real user feedback

Ready to Streamline Your Engineering Workflow?

EngiToolbox is built by one engineer obsessed with getting the details right. Use every core tool free — and if it saves you time, going Pro keeps the project independent and growing.

Get Started Now

All calculations are provided for reference only. Always verify results according to your specific engineering requirements.