# PrecisionCalc MCP server

> Provides high-precision business and financial calculations for AI agents using exact decimal math instead of floats.

- Repository: https://github.com/inity13/precisioncalc-mcp
- Page: https://hostedmcp.org/servers/inity13/precisioncalc-mcp
- Transport: stdio, remote
- Stars: 0
- License: MIT
- Latest version: 2.1.1

## Install

### Claude Code

```sh
claude mcp add precisioncalc-mcp -- npx -y precisioncalc-mcp
```

### Cursor (`~/.cursor/mcp.json`)

```json
{
  "mcpServers": {
    "precisioncalc-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "precisioncalc-mcp"
      ]
    }
  }
}
```

### VS Code (`.vscode/mcp.json`)

```json
{
  "servers": {
    "precisioncalc-mcp": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "precisioncalc-mcp"
      ]
    }
  }
}
```

### VS Code CLI

```sh
code --add-mcp '{"name":"precisioncalc-mcp","type":"stdio","command":"npx","args":["-y","precisioncalc-mcp"]}'
```

### Claude Desktop (`claude_desktop_config.json`)

```json
{
  "mcpServers": {
    "precisioncalc-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "precisioncalc-mcp"
      ]
    }
  }
}
```

### Codex

```sh
codex mcp add precisioncalc-mcp -- npx -y precisioncalc-mcp
```

### Codex config.toml (`~/.codex/config.toml`)

```toml
[mcp_servers.precisioncalc-mcp]
command = "npx"
args = ["-y", "precisioncalc-mcp"]
```

### Gemini CLI

```sh
gemini mcp add -s user precisioncalc-mcp npx -- -y precisioncalc-mcp
```

### Gemini settings.json (`~/.gemini/settings.json`)

```json
{
  "mcpServers": {
    "precisioncalc-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "precisioncalc-mcp"
      ]
    }
  }
}
```

## Environment variables

| Name | Required | Secret | Description |
|---|---|---|---|
| `PRECISIONCALC_API_KEYS` | no | no |  |

## Tools (14)

- `ltv`
- `cac`
- `ltv_cac_ratio`
- `payback_period_months`
- `contribution_margin`
- `gross_margin`
- `churn_rate`
- `mrr_growth_rate`
- `arr`
- `break_even_units`
- `nrr`
- `grr`
- `rule_of_40`
- `magic_number`

## FAQ

### How does the server handle decimal precision?

The server uses Python's decimal module to ensure exact calculations for monetary and financial values, avoiding the inaccuracies of floating-point math.

### What kind of business metrics can I calculate?

It supports 14 SaaS and business metrics including LTV, CAC, churn, MRR growth, NRR, GRR, Rule of 40, and more.

### Can I use live currency exchange rates?

Yes, the server supports live and historical FX rates via the ECB (Frankfurter) provider.

### Does it support international business day logic?

Yes, it can add or count business days for the US, UK, EU, or any ISO country code.