Simple, engineer-friendly pricing

Every calculator stays usable for free. Pro and Team remove on-site advertising and unlock PDF exports, unlimited saves, advanced modes, the API, and live access to our premium engineering solvers.

Free
£0forever
  • Every calculator usable — formulas, FAQs & diagrams
  • 3 saved calculations
  • Worked-example previews on Pro solvers
  • Community support
  • Ad-supported browsing
Browse calculators
Pro
£12/month
  • Live premium solvers (O-ring sizing, bridge designer)
  • Ad-free browsing across the site
  • Branded PDF report exports
  • Unlimited saved calculations
  • Advanced calculator modes
  • Full calculator REST API (1,000 requests/month)
Team
£49/month
  • Everything in Pro
  • Shared team workspace
  • Full calculator REST API (10,000 requests/month)
  • Priority support

Building an integration? Explore the developer API docs. Need white-label or enterprise API? Contact us for licensing