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.

Decide before calling

Read the versioned contract and the supported scope below. Reuse length-convert@1.0.0 when your input, required output and limits match it. Choose another approach for an unsupported operation.

Explain the choice

"I can use length-convert@1.0.0 for length convert. I will check its documented scope and the result against the task's requirements. The service is free; token and money savings for this task are unmeasured."

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/.

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