Return the new monthly payment, monthly savings, total cost of the current vs the new loan, total savings, break-even month, and whether a mortgage refinance is worth it. Closing costs are added to the new loan balance. Rates are yearly percentages. Give current_monthly_payment, or give current_rate and it is computed from the balance and the remaining months.
This page documents the MCP tool findutils:refinance_calculator. See the REST reference →
Call it over MCP
Tool name findutils:refinance_calculator
· no API keys · 120 requests/min per IP
Claude Code
claude mcp add findutils --transport http https://mcp.findutils.com/Claude Desktop — claude_desktop_config.json
{
"mcpServers": {
"findutils": {
"url": "https://mcp.findutils.com/"
}
}
}Raw JSON-RPC (any MCP client) — verified example
curl -X POST https://mcp.findutils.com/ \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "refinance_calculator",
"arguments": {
"current_balance": 250000,
"current_monthly_payment": 1580,
"remaining_months": 300,
"new_rate": 5.5,
"new_term_months": 360,
"closing_costs": 5000
}
}
}'Input schema
| Argument | Type | Required | Description |
|---|---|---|---|
| current_balance | number | yes | Remaining balance on the current loan. Must be > 0. |
| current_monthly_payment | number | no | Current monthly payment. Optional when current_rate is given. |
| current_rate | number | no | Current yearly rate in percent. Used only to compute a missing current_monthly_payment. |
| remaining_months | integer | yes | Months left on the current loan. |
| new_rate | number | yes | New yearly rate in percent. |
| new_term_months | integer | yes | New loan term in months (360 = 30 years). |
| closing_costs | number | no | Refinance closing costs. Default: 0. |
Example arguments (verified)
{
"current_balance": 250000,
"current_monthly_payment": 1580,
"remaining_months": 300,
"new_rate": 5.5,
"new_term_months": 360,
"closing_costs": 5000
}Also a REST endpoint
The same tool answers plain HTTP at
POST /api/tools/refinance-calculator/execute — no key, 60 requests/min.
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