calc.engineer / General & Math / Unit Convert

Unit Convert v1.0.0

Convert between units across 10 categories: length (m, km, mi, ft, in, yd, nmi), mass (kg, lb, oz, g, ton), volume (l, gal, ml, cup, fl_oz), area (m2, ft2, acre, hectare), speed (mps, kph, mph, knot), pressure (pa, psi, bar, atm, mmhg), energy (j, kwh, btu, cal, wh), data (b, kb, mb, gb, tb), time (s, ms, min, hr, day, year), and temperature (c, f, k). Accepts any value with source and target unit abbreviations. Returns the converted result with the formula used.

The numeric value to convert.
Source unit abbreviation (e.g., 'km', 'lb', 'f', 'psi', 'kwh'). Case-insensitive.
Target unit abbreviation (e.g., 'mi', 'kg', 'c', 'bar', 'btu'). Case-insensitive.
Fill in the inputs and Compute to see the structured result.

From an agent (MCP) or the API

curl -X POST https://calc.engineer/api/unit_convert \
  -H "Content-Type: application/json" \
  -d '{"value": …, "from": …, "to": …}'

MCP: connect to https://calc.engineer/mcp and call unit_convert.

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