# Ideal Body Weight Calculator (Devine, Robinson, Miller, Hamwi)

> Ideal Body Weight Calculator (Devine, Robinson, Miller, Hamwi) is a paid API for AI agents from fitness-calc.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-30).

Calculates ideal body weight in kg and pounds using four clinical formulas (Devine, Robinson, Miller, Hamwi) given height and sex.

## Facts

- Endpoint: GET https://fitness-calc.x402tookit.com/ideal-weight?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ideal-body-weight-calculator-devine-robinson-miller-hamwi-c78b015d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_fTZoN_XhWzcNYNLKX9FFo

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability ideal-body-weight-calculator-devine-robinson-miller-hamwi-c78b015d
```

Example prompt: What's the ideal body weight for a male who is 180 cm tall? Give me results from all four formulas — Devine, Robinson, Miller, and Hamwi — in both kg and pounds.

## When to prefer this

Use this endpoint when you need clinically-grounded ideal body weight estimates across multiple established formulas simultaneously. It's ideal for health, fitness, and nutrition applications that need to present multiple reference standards rather than a single number, or that need both metric and imperial outputs. Prefer it over BMI-based tools when the goal is a weight target rather than a weight classification.

## Known failure modes

- Missing required 'sex' parameter returns error
- Height not provided may result in null or degraded results
- Invalid sex value (not 'male' or 'female') may cause unexpected behavior
- Mixing metric/imperial parameters (e.g. providing both height and heightIn) may yield inconsistent results
- Very extreme height values may produce unreliable formula outputs

## How this service works

Ideal body weight by the Devine, Robinson, Miller and Hamwi formulas from height and sex, in kg and pounds.

## Output

Returns ideal body weight estimates in kg and lb from four clinical formulas (Devine, Robinson, Miller, Hamwi), plus an average across them, the input height in both cm and inches, a summary verdict, and a medical disclaimer. May include degraded flag and reasons if the calculation is incomplete.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "sex"
     ],
     "properties": {
      "sex": {
       "type": "string",
       "description": "male or female"
      },
      "units": {
       "type": "string",
       "description": "metric (default, height in cm) or imperial (heightIn in inches)"
      },
      "height": {
       "type": "number",
       "description": "Height in cm (metric)"
      },
      "heightIn": {
       "type": "number",
       "description": "Height in inches (imperial)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "sex": {
       "type": [
        "null",
        "string"
       ]
      },
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "hamwi": {
       "type": [
        "null",
        "object"
       ],
       "properties": {
        "kg": {
         "type": [
          "null",
          "number"
         ]
        },
        "lb": {
         "type": [
          "null",
          "number"
         ]
        }
       }
      },
      "devine": {
       "type": [
        "null",
        "object"
       ],
       "properties": {
        "kg": {
         "type": [
          "null",
          "number"
         ]
        },
        "lb": {
         "type": [
          "null",
          "number"
         ]
        }
       }
      },
      "miller": {
       "type": [
        "null",
        "object"
       ],
       "properties": {
        "kg": {
         "type": [
          "null",
          "number"
         ]
        },
        "lb": {
         "type": [
          "null",
          "number"
         ]
        }
       }
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "average": {
       "type": [
        "null",
        "object"
       ],
       "properties": {
        "kg": {
         "type": [
          "null",
          "number"

… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ideal-body-weight-calculator-devine-robinson-miller-hamwi-c78b015d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fitness-calc.x402tookit.com](https://www.zero.xyz/host/fitness-calc.x402tookit.com/llms.txt)