Geography
Great Circle Distance Calculator
Calculate the shortest distance between two points on Earth using the great circle formula
json· JSON resultOpen tool
Quick start
Call this tool from your code in three languages.
cURL
curl -X POST 'https://api.elysiatools.com/en/api/tools/great-circle-distance' \
-H 'Content-Type: application/json' \
-d '{"lat1":40.7128,"lon1":-74.006,"lat2":51.5074,"lon2":-0.1278,"unit":"km","precision":2}'API reference
Send a POST request with your inputs as JSON. File parameters require a separate upload first.
Endpoint
HTTP
POST https://api.elysiatools.com/en/api/tools/great-circle-distanceParameters
| Name | Type | Required | Description |
|---|---|---|---|
| lat1 | number | Yes | — |
| lon1 | number | Yes | — |
| lat2 | number | Yes | — |
| lon2 | number | Yes | — |
| unit | select | No | — |
| precision |
MCP integration
Add this tool to your Model Context Protocol server so AI agents can list and call it.
Server configuration
Add this block to your MCP client configuration:
mcp.json
{
"mcpServers": {
"elysiatools-great-circle-distance": {
"name": "great-circle-distance",
"description": "Calculate the shortest distance between two points on Earth using the great circle formula",
"baseUrl": "https://api.elysiatools.com/mcp/sse?toolId=great-circle-distance",
"command": "",
"args": [],
"env": {},
"isActive": true,
"type": "sse"
}
}
}List available tools
After connecting to the SSE endpoint, list the exposed tools:
tools/list
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/list"
}Call this tool
Invoke the tool by its id, passing arguments built from its parameters:
tools/call
{
"jsonrpc": "2.0",
"id": 2,
"method": "tools/call",
"params": {
"name": "great-circle-distance",
"arguments": {
"lat1": 40.7128,
"lon1": -74.006,
"lat2": 51.5074,
"lon2": -0.1278,
"unit": "km",
"precision": 2
}
}
}Chain multiple tools in one session with a comma-separated toolId list, e.g. /mcp/sse?toolId=png-to-webp,jpg-to-webp,gif-to-webp (max 20).
Questions or issues? Contact [email protected]