Wardian Unit converter
Try it
The app runs here in your browser. Nothing you type leaves it. Open it on its own.
Download unit-converter.wardian Import it in Wardian: Settings → Import.
A Wardian module app: 32 everyday conversions, each one a WebAssembly function of numbers. There is no page. Wardian reads the module's exports and draws a card for each function, with an input per parameter and a Run button.
Why a module: every conversion takes numbers and returns a number. That is exactly what a module
app shows without help, so the whole interface comes from src/lib.rs. No HTML, no JavaScript.
| File | What it is |
|---|---|
src/lib.rs | The conversions. Each #[no_mangle] pub extern "C" fn becomes a card in Wardian. Unit tests at the end. |
app.wasm | The module Wardian runs, about 2 KB. Built from src/lib.rs. |
app.json | The title and the description in the app list. |
build.sh | Rebuilds app.wasm. |
| Group | Functions |
|---|---|
| Temperature | c_to_f, f_to_c, c_to_k, k_to_c |
| Length | km_to_miles, miles_to_km, m_to_feet, feet_to_m, cm_to_inches, inches_to_cm, feet_inches_to_cm(feet, inches) |
| Mass | kg_to_lb, lb_to_kg, g_to_oz, oz_to_g |
| Volume (US) | liters_to_gallons, gallons_to_liters, ml_to_floz, floz_to_ml |
| Speed and fuel | kmh_to_mph, mph_to_kmh, mpg_to_l_per_100km, l_per_100km_to_mpg |
| Pressure | kpa_to_psi, psi_to_kpa, bar_to_psi |
| Power and energy | kw_to_hp, hp_to_kw, kcal_to_kj, kj_to_kcal |
| Body | bmi_kg_m(weight_kg, height_m), bmi_lb_in(weight_lb, height_in) |
How data moves: you type a number in a card and press Run (or Enter). Wardian calls the function with a JavaScript number, the module returns a 64-bit float, and Wardian shows it under the card. Nothing leaves the browser.
Names carry the units, because Wardian labels the inputs only "arg 1", "arg 2". So
km_to_miles takes kilometres, and a function with two inputs names them in order:
bmi_kg_m takes the weight in kilograms first, then the height in metres.
Limits:
- Results are rounded to 4 decimal places (BMI to 1), so 37 °C shows as 98.6 and not 98.60000000000001.
- Gallons and fluid ounces are US units. The factors are the exact legal definitions (1 mile = 1.609344 km, 1 lb = 0.45359237 kg, 1 US gallon = 3.785411784 L).
bmi_kg_mreturns 0 when the height is 0 or less. The fuel functions return 0 for 0 or less.- Horsepower is mechanical horsepower (745.7 W), not metric.
Change it: edit src/lib.rs, run cargo test, run ./build.sh, then wardian check ..
This page is apps/unit-converter/README.md in the repository. Something wrong or missing? Change that file.