# Home Affordability Calculator API

> For the complete documentation index, see [llms.txt](/llms.txt).

Maximum home price under the 28/36 rule with the full escrow breakdown and DTI ratios.

Use this endpoint to add the tool to your app, site, workflow, or agent without rebuilding formulas, validation, examples, and docs.

- Slug: `home-affordability-calculator`
- Category: `finance`
- Version: `2026-04-22`
- Credits per successful call: 2
- Starts on: free
- Max payload: 65536 bytes
- Privacy mode: `hash_only`
- Available on: free, starter, pro, business, scale
- Browser tool: https://miniwebtool.com/home-affordability-calculator/

## Endpoint

`POST https://api.miniwebtool.com/v1/tools/home-affordability-calculator/run`

## Request body

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `annual_income` | `float` | no | gross annual household income |
| `monthly_debt` | `float` | no | existing monthly debt payments |
| `down_payment` | `float` | no | cash down payment |
| `interest_rate` | `float` | no | annual mortgage rate % |
| `loan_term` | `str` | no | 30 | 20 | 15 | 10 Choices: 30, 20, 15, 10 |
| `property_tax_rate` | `float` | no | annual property tax as % of value |
| `annual_insurance` | `float` | no | annual homeowners insurance, 0 to estimate |
| `monthly_hoa` | `float` | no | monthly HOA fees |

## Example request

```json
{
  "annual_income": 90000,
  "monthly_debt": 500,
  "down_payment": 60000,
  "interest_rate": 6.5,
  "loan_term": "30",
  "property_tax_rate": 1.1,
  "annual_insurance": 0,
  "monthly_hoa": 0
}
```

## cURL

```bash
curl -X POST https://api.miniwebtool.com/v1/tools/home-affordability-calculator/run \
  -H 'Authorization: Bearer mwt_live_YOUR_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"annual_income":90000,"monthly_debt":500,"down_payment":60000,"interest_rate":6.5,"loan_term":"30","property_tax_rate":1.1,"annual_insurance":0,"monthly_hoa":0}'
```

## Response envelope

```json
{
  "request_id": "01K...",
  "tool": "home-affordability-calculator",
  "tool_version": "2026-04-22",
  "credits_used": 2,
  "result": {}
}
```

## Errors

Errors are RFC 7807 `application/problem+json`. Branch on `code`, not `title`.

## MCP

Agents can discover and call this tool through `https://api.miniwebtool.com/mcp` or `https://api.miniwebtool.com/v1/mcp` using MCP `tools/list` and `tools/call`.

## Frequently asked

### What does the Home Affordability Calculator API do?

Maximum home price under the 28/36 rule with the full escrow breakdown and DTI ratios. Use it to add this utility without rebuilding formulas, validation, examples, and documentation.

### How much does one call cost?

2 credits per successful call. Failed calls do not bill.

### What parameters are required?

Required fields: (none). Full schema at `https://api.miniwebtool.com/v1/openapi.json`.

### Is this deterministic?

Yes. Same input, same output. Tool version: 2026-04-22.