← All endpoints
mortgage-amortization.underscoredone.com calculate
https://mortgage-amortization.underscoredone.com/calculate
answers 402
Give this API a loan amount, an interest rate, and a repayment term, and it hands back the precise monthly payment plus a complete schedule showing — for every single month — how much goes to interest, how much reduces the balance, and what you still owe. You can also ask 'what if I pay an extra $300 a month?' or 'what if I make a $10,000 lump payment in month 24?' and it will tell you exactly how
We sent a real
POST request to this endpoint and it
answered 402 with payment requirements we could parse.
- Price
- $0.01
- Network
- base
- Pay to
- 0xE9740820225B3918b4ddd1292C7cA4Ca0e2C2F08
- Spec dialect
- v2 (declares x402Version 2)
- Transport
- PAYMENT-REQUIRED header
- HTTP method
- POST
- Response latency
- 108 ms
- Payment options
- 2 usable of 2
- Last checked
- 2026-08-15T14:22:50.601Z (16h ago)
- Category
- finance-crypto
Re-check it yourself:
curl "https://api.the402.dev/validate?url=https%3A%2F%2Fmortgage-amortization.underscoredone.com%2Fcalculate"