Hydraulic & Pneumatic Calculator

Free, open-source calculators for hydraulic and pneumatic system design. Pump flow, cylinder force, motor torque, accumulator sizing, buckling, thread identification and more, in one app that runs in the browser and on Android.

Use it now: calculate.hidroteknik.com.tr · Android app

Built by Hidroteknik, a hydraulics and pneumatics manufacturer and distributor in Denizli, Türkiye, operating since 1984. These are the calculations our own engineers and service technicians use every day.

Modules

Module	What it calculates
Hydraulic System	Pressure, flow, power, cylinder push/pull force and speed (F = P × A)
Advanced Hydraulic System	Multi-cylinder systems: stage-by-stage pump, motor and tank sizing
Buckling & Shaft Diameter	Euler critical load and minimum rod diameter, four end conditions
Gear Pump Selection	Pump selection by flow, pressure and motor power
Pipe & Rod Weight	Weight per metre by material and size
Pneumatic Cylinder	Force, air flow and air consumption
Hydraulic Motor	Torque, power and speed
Thread & Pitch Standards	Identify Metric, BSP, NPT, UNF and UNC threads from measurements
Pipe Unit Converter	DN, inch and mm conversions with a pipe table
Pressure Converter	bar, psi, MPa, kPa, atm, mmHg
Flow Velocity	Line sizing by recommended flow velocity
Accumulator Sizing	Accumulator volume and nitrogen pre-charge (Boyle's law)

Every module is available in English and Turkish. Each one also has a step-by-step calculation guide with the formulas explained.

Tech stack

• Expo (React Native) with a single codebase for Android and web
• React Navigation (drawer + stack), i18next for TR/EN
• Web build deployed on Vercel (npx expo export -p web)
• Android builds via EAS
• Static, SEO-friendly guide pages generated by scripts/gen-guides.js into public/guide/

Run locally

You need Node.js 20 or newer.

npm install
npm run web        # opens the app in your browser
npm run android    # Android emulator or device (Expo Go)

Build the static web version:

npx expo export -p web   # output in dist/

Project structure

App.tsx                  entry point
src/
  screens/               one screen per calculator module
  components/            shared UI (results, tooltips, diagrams)
  components/diagrams/   SVG diagrams (cylinder, accumulator, buckling, pipes, threads)
  data/                  gear pump and thread standard tables
  i18n/locales/          en.json, tr.json
  navigation/            drawer and stack navigation
scripts/                 guide page and app icon generators
public/guide/            generated calculation guides

Contributing

Found a wrong result, a missing standard or a formula you'd like added? Open an issue. Please include the inputs you used and the value you expected. Pull requests are welcome, especially new modules and translations.

Disclaimer

Results are for preliminary design and reference. Always verify critical calculations against manufacturer data and applicable standards.

License

Source code: MIT © 2026 Hidroteknik A.Ş. The Hidroteknik name, logo and photographs are not covered by the license.