📏Length Converter
Convert between metric and imperial length units: kilometers, meters, centimeters, millimeters, micrometers, nanometers, miles, yards, feet, inches and nautical miles.
Worked examples
1 Kilometers in Meters
GET /api/v1/converters/length-converter?value=1&from=km&to=m
Result: 1,000 m
100 Kilometers in Meters
GET /api/v1/converters/length-converter?value=100&from=km&to=m
Result: 100,000 m
5 Meters in Kilometers
GET /api/v1/converters/length-converter?value=5&from=m&to=km
Result: 0.005 km
2 Kilometers in Centimeters
GET /api/v1/converters/length-converter?value=2&from=km&to=cm
Result: 200,000 cm
Machine API (x402)
$0.001 / callThis tool is also a JSON API for AI agents. Requests without payment receive 402 Payment Required plus instructions; agents pay USDC on Base via the x402 protocol — no accounts, no API keys.
GET /api/v1/converters/length-converter?value=1&from=km&to=m HTTP/1.1
Host: agenttools-hub.vercel.app
→ 402 (payment required, instructions in headers)
→ 200 (after X-PAYMENT header; JSON body below)
{
"tool": "converters/length-converter",
"input": {"value":1,"from":"km","to":"m"},
"result": { "value": 1000, "answer": "1,000 m" }
}Agent docs: /llms.txt · OpenAPI spec · integration guide
About this tool
Convert any length or distance unit to any other with exact international definitions — miles, kilometers, feet, inches, nautical miles and the metric scale from nanometers to kilometers.
value × kmfactor ÷ target factor (all units relate to the m base)
Frequently asked questions
How many kilometers in a mile?
One mile is exactly 1.609344 kilometers by international agreement since 1959.
How many feet in a meter?
One meter is 3.28084 feet (or about 3 ft 3.37 in).
What is a nautical mile?
One nautical mile is exactly 1,852 meters — one arc-minute of latitude, used in aviation and marine navigation.