Over 2,400 engineering calculators in one place — hydraulics, heating, ventilation, mechanics, geometry, and more, with 1,900+ machine-precision links connecting related tools. Free, no sign-up, no install. Just a browser.
A growing library of single-purpose calculators, each built around one formula or one engineering question. No spreadsheets, no plugins — just open the page, type values, get a result.
Reynolds number, pressure drop, NPSH, pipe sizing, flow regimes — 457 calculators across hydraulics, ventilation, and HVAC.
Heat transfer, U-values, psychrometrics, combustion — 365 thermodynamics calculators plus 305 heating-industry tools.
Beam equations, stress and strain, shaft sizing, bolted joints — 304 mechanics + 265 statics calculators.
Areas, volumes, regression (MNK), unit conversions — 217 geometry + 317 math calculators with clean inputs.
Battery sizing, cable cross-sections, plus chemistry, materials science, acoustics — 200+ calculators across the rest of physics.
Built-in i18n for Polish, English, German, French, Spanish, and more. Numbers and units adapt to locale.
1,900+ machine-precision links connect related calculators — when an output of one is the input of another, jump straight to the next step in your calculation.
| Physics | 934 |
|---|---|
| Fluid mechanics | 457 |
| District heating & HVAC | 305 / 99 / 181 |
| Thermodynamics | 365 |
| Hydraulics | 240 |
| Construction | 351 |
| Mechanics & statics | 304 / 265 |
| Geometry & math | 217 / 317 |
| Chemistry | 150 |
| Materials science | 67 |
| Electrical | 156 |
| Acoustics, numerics, OZE, 3D printing, ... | 100+ |
Counts as of last database export. Each calculator may belong to multiple categories.
| Stack | Vanilla HTML, CSS, JavaScript (ES6+, Web Components) |
|---|---|
| Formulas | mathjs (declarative defineCalculator runtime) |
| Languages | 12 (i18n built-in) |
| Build step | None — pages load instantly, no framework. |
| Price | Free, forever. Donations optional. |
No sign-up, no install, no payment. Bookmark kalkulator.modeltok.com and you're done.