Calc MCP runs on your own machine — the client starts it, so there is no endpoint to ping. 107 installs a week from npm. Last commit 7 Nov 2026.
21 MCP tools for math, randomness, dates, encoding, hashing, and more — deterministic and accurate.
Today is the operative word: we check Calc MCP every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.
This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.
claude mcp add calc-mcp -- npx -y @coo-quack/calc-mcp
{
"mcpServers": {
"calc-mcp": {
"command": "npx",
"args": [
"-y",
"@coo-quack/calc-mcp"
]
}
}
}
[mcp_servers.calc-mcp]
command = "npx"
args = ["-y", "@coo-quack/calc-mcp"]
{
"mcpServers": {
"calc-mcp": {
"command": "npx",
"args": [
"-y",
"@coo-quack/calc-mcp"
]
}
}
}
{
"servers": {
"calc-mcp": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@coo-quack/calc-mcp"
]
}
}
}
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