# Macro Calculator — MCP tool `findutils:macro_calculator`

Calculate daily calorie needs and a macronutrient split (protein, carbs, fat in grams and kcal) for weight loss, maintenance, or muscle gain. Uses Mifflin-St Jeor BMR, an activity multiplier, a +/-500 kcal goal adjustment, and goal-specific ratios.

- Category: calculators
- MCP server: https://mcp.findutils.com/ (Streamable HTTP, no API keys, 120 req/min per IP)
- REST endpoint: POST https://api.findutils.com/api/tools/macro-calculator/execute (no API keys, 60 req/min per IP)
- Reference page: https://findutils.com/mcp/macro-calculator/
- Same tool on the other surface: https://findutils.com/api/macro-calculator/

## Connect

```bash
claude mcp add findutils --transport http https://mcp.findutils.com/
```

Claude Desktop (`claude_desktop_config.json`):

```json
{
  "mcpServers": {
    "findutils": {
      "url": "https://mcp.findutils.com/"
    }
  }
}
```

## Call the tool (verified example)

```bash
curl -X POST https://mcp.findutils.com/ \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "macro_calculator",
      "arguments": {
        "gender": "male",
        "age": 30,
        "weight": 70,
        "height": 175
      }
    }
  }'
```

## Input schema

| Argument | Type | Required | Description |
|---|---|---|---|
| `gender` | string (male \| female) | yes | Biological sex used by the BMR equation. |
| `age` | integer | yes | Age in years (1-120). |
| `weight` | number | yes | Body weight in kg (metric) or lbs (imperial). |
| `height` | number | yes | Height in cm (metric) or inches (imperial). |
| `unit_system` | string (metric \| imperial) | no | Unit system for weight and height. Default: `"metric"`. |
| `activity_level` | string (sedentary \| light \| moderate \| active \| very_active) | no | Activity level: sedentary 1.2, light 1.375, moderate 1.55, active 1.725, very_active 1.9. Default: `"moderate"`. |
| `goal` | string (lose \| maintain \| gain) | no | lose = -500 kcal with 35/35/30 split, maintain = 30/40/30, gain = +500 kcal with 25/50/25 (protein/carbs/fat). Default: `"maintain"`. |

Example arguments (verified):

```json
{
  "gender": "male",
  "age": 30,
  "weight": 70,
  "height": 175
}
```

## Also a REST endpoint

```bash
curl -X POST https://api.findutils.com/api/tools/macro-calculator/execute \
  -H "Content-Type: application/json" \
  -d '{
    "gender": "male",
    "age": 30,
    "weight": 70,
    "height": 175
  }'

# Parameter schema
curl https://api.findutils.com/api/tools/macro-calculator
```

Full REST reference: https://findutils.com/api/macro-calculator/ · OpenAPI 3.1 spec: https://findutils.com/api/openapi.json

---
Full catalog: POST https://mcp.findutils.com/ with method `tools/list` · https://findutils.com/mcp/ · https://findutils.com/llms.txt