Loan payoff calculator

Calculate loan payoff calculator with clear inputs and assumptions.

Your inputs stay in your browser. Displayed results are rounded to a maximum of 12 significant digits.

Method and assumptions

Method version 1.0.0 · Updated October 17, 2026

Calculate

Formula: Calculate loan payoff calculator with clear inputs and assumptions.

Calculate loan payoff calculator with clear inputs and assumptions.

balance: Remaining balance
payment: Monthly payment
rate: Annual rate (%)

Results are estimates where noted and depend on the entered assumptions.

Calculate with code

These short examples use the same inputs and core calculation as this tool. Adapt validation and formatting to your application.

JavaScript

const balance = 12000, payment = 400, rate = 0.06 / 12;
const months = Math.ceil(-Math.log(1 - balance * rate / payment) / Math.log(1 + rate));
console.log(months); // about 33 payments

TypeScript

const balance = 12000, payment = 400, rate = 0.06 / 12;
const months: number = Math.ceil(-Math.log(1 - balance * rate / payment) / Math.log(1 + rate));
console.log(months);

Python

import math
balance, payment, rate = 12000, 400, 0.06 / 12
print(math.ceil(-math.log(1 - balance * rate / payment) / math.log(1 + rate)))

Java

double b = 12000, p = 400, r = 0.06 / 12;
System.out.println(Math.ceil(-Math.log(1 - b * r / p) / Math.log(1 + r)));

double b = 12000, p = 400, r = 0.06 / 12;
Console.WriteLine(Math.Ceiling(-Math.Log(1 - b * r / p) / Math.Log(1 + r)));