Length convert

length-convert · version 1.0.0 · Units & sizes · free, no key needed

Convert a canonical integer length between exact SI and international customary units.

Use when you need to: length convert · convert length units · convert integer length between units.

Supported

length convert
convert length units
convert integer length between units

Not supported

nautical miles
survey feet
SI prefixes other than nm um mm cm m km
floating-point lengths

Behavior

value is a canonical integer string amount in the from unit and may be negative.
from and to are exactly one of nm, um, mm, cm, m, km, in, ft, yd, mi using the LENGTH_NM table.
The result is the reduced rational (value * from_nm) / to_nm expressed in to units.
Sign lives only on the numerator; zero is numerator 0 over denominator 1.
Input integers and the reduced numerator and denominator may have at most 1000 digits excluding sign.

Input

value (string, required): max length 1001; pattern ^-?(0|[1-9][0-9]*)$
from (one of "nm", "um", "mm", "cm", "m", "km", "in", "ft", "yd", "mi", required)
to (one of "nm", "um", "mm", "cm", "m", "km", "in", "ft", "yd", "mi", required)

Output

numerator (string, required): pattern ^(0|-?[1-9][0-9]*)$
denominator (string, required): pattern ^[1-9][0-9]*$

Limits

max digits: 1000
units: ["nm","um","mm","cm","m","km","in","ft","yd","mi"]

Example

Request input:

{
  "value": "1",
  "from": "ft",
  "to": "in"
}

Response:

{
  "result": {
    "numerator": "12",
    "denominator": "1"
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "length-convert",
  "version": "1.0.0",
  "input": {
    "value": "1",
    "from": "ft",
    "to": "in"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/length-convert/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"value":"1","from":"ft","to":"in"}'

The machine-readable contract is at /v1/tools/length-convert/versions/1.0.0.

CLI

node cli.mjs run length-convert 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

Byte size convert: Convert a non-negative integer byte size between IEC binary units as an exact rational.
Length compare: Compare two integer length measurements by exact nanometer amounts.
Mass convert: Convert a canonical integer mass amount between exact nanogram-based units as a reduced rational.
Temperature convert: Convert a decimal temperature between Celsius, Fahrenheit, and Kelvin as an exact rational.
Length add: Add integer length terms in mixed units and return the exact sum in a chosen unit.
Mass add: Add mixed-unit canonical integer mass amounts and express the sum in a target unit as a reduced rational.