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Loan Payment Calculator

Accurately estimate your monthly loan payments, total interest costs, and repayment timelines with clear payment schedules and transparent mathematical breakdowns.

Loan Payment Workspace

Input your principal loan amount, annual interest rate, and repayment term to instantly project flat monthly installments and total borrowing costs.

Loan Calculator

Enter a loan amount, annual interest rate, and term to estimate the monthly payment and total loan cost.

$
Please enter a valid loan amount greater than 0.
%
Interest rate cannot be negative.
Loan term must be greater than zero.
$
$
Estimated Monthly Payment
$1,896.20
Fixed monthly principal & interest
Total Payment
$682,633.47
Total Interest
$382,633.47
Number of Payments
360
Loan Term
30 Years
Loan Cost Breakdown Principal 44% / Interest 56%
Principal: $300,000.00
Interest: $382,633.47
First Payment: Month 1 Payoff Timeline: Month 360

How the Loan Payment Is Calculated

1. Monthly Interest Rate (r)
= 6.5% ÷ 12 = 0.541667% (0.005417)
2. Total Number of Payments (n)
= 30 years × 12 months = 360 payments
3. Standard Amortization Formula
M = P × r / (1 - (1 + r)^(-n))
4. Step-by-Step Substitution
M = 300,000 × 0.005417 / (1 - (1 + 0.005417)^(-360)) = $1,896.20
Estimates are for informational purposes only and may differ from actual lender terms, fees, and charges.

How to Use the Loan Calculator

Plan your borrowing and visualize repayment schedules in four straightforward steps:


01

Enter Loan Amount (P)

Enter the total amount of money you intend to borrow or finance after subtracting any down payment.

02

Set Annual Interest Rate (r)

Input the annual percentage rate (APR) charged by your bank or lending institution.

03

Choose Loan Term (Years/Months)

Select the duration over which you plan to pay off the loan balance (e.g., 5 years, 15 years, or 30 years).

04

View Payments & Schedule

Instantly review your estimated monthly payment, overall interest charges, and dynamic payoff schedule.

FORMULA & EXPLANATION

The Math Behind Loan Amortization

Financial institutions globally rely on the standard fixed-rate amortization formula to calculate flat periodic payments across compounding periods.

Standard Monthly Payment (EMI) Formula Amortization Equation
Monthly Payment (M) = P ×
r(1 + r)n (1 + r)n − 1

P

Principal Loan Amount (P)

The total balance borrowed before interest calculations.

n

Monthly Interest Rate (r)

The annual nominal rate divided by 12 months and 100 (r=APR/1200).

n

Total Number of Payments (n)

The total months across the term (Years×12).

M

Monthly Payment (M)

The fixed periodic installment combining principal reduction and accrued interest.

Real-World Loan Scenarios

Practical examples demonstrating how different terms and interest rates impact total borrowing costs.

5-Year Auto / Car Loan

Financing a vehicle purchase of $25,000 at an annual interest rate of 6% over 5 years (60 months).


Given: Principal = $25,000, APR = 6% (r=0.005), Term = 60 months

Calculation:Monthly Payment (M) ≈$483.32Total Repayment = $483.32×60=$28,999.20

Answer: Total interest paid is $3,999.20 with monthly installments of $483.32.

3-Year Personal Loan

Taking an unsecured personal loan of $10,000 at a fixed rate of 8% over 3 years (36 months).


Given: Principal = $10,000, APR = 8% (r=0.00667), Term = 36 months

Calculation:Monthly Payment (M) ≈$313.36Total Repayment = $313.36×36=$11,280.96

Answer: Total interest paid is $1,280.96 with monthly installments of $313.36.

15-Year Fixed Home Mortgage

Borrowing $200,000 for a home purchase at 6.5% interest on a 15-year term (180 months).


Given: Principal = $200,000, APR = 6.5% (r=0.00542), Term = 180 months

Calculation:Monthly Payment (M) ≈$1,742.22Total Repayment = $1,742.22×180=$313,599.60

Answer: Total interest paid is $113,599.60 with monthly installments of $1,742.22.

Compare Loan Terms: How Term Length Affects Your Payment

The same loan amount and interest rate can cost very differently depending on how long you take to pay it off. Here's how a $300,000 loan at 6.5% APR compares across three common terms.

10-Year Term
20-Year Term
30-Year Term
Monthly Payment
$3,406
$2,237
$1,896
Total Interest Paid
$108,778
$236,846
$382,633
Total Cost
$408,778
$536,846
$682,633
Takeaway
Highest monthly payment, lowest total interest
Balanced middle ground
Lowest monthly payment, but pays more than the original loan amount in interest alone

Loan Basics: What Affects Your Payment

How Loan Term Affects Your Total Cost

A longer loan term lowers your monthly payment but increases the total interest you pay, since interest accrues over more periods. A shorter term raises your monthly payment but reduces total interest significantly. See the comparison table above for real numbers side by side.

How Compounding Frequency Affects Interest

Most installment loans (mortgages, auto loans, personal loans) use monthly compounding, meaning interest is calculated and added to your balance once per period. Choosing a more frequent payment schedule, like biweekly, in the calculator above doesn't change the compounding method itself, but it does mean you're paying down principal more often, which can reduce total interest slightly.

Secured vs. Unsecured Loans

A secured loan is backed by collateral, like a house for a mortgage or a car for an auto loan. If you default, the lender can seize the asset. Because the risk to the lender is lower, secured loans typically carry lower interest rates. An unsecured loan, like most personal loans and credit cards, has no collateral backing it, so lenders charge higher rates to offset their risk.

Frequently Asked Questions

Everything you need to know about loan amortization, interest calculations, and payoff planning.

What is the difference between simple interest and amortized loan interest?

Simple interest is calculated solely on the original principal throughout the entire term. Amortized interest, used in most mortgages, personal, and auto loans, calculates interest each month on the remaining unpaid principal balance, meaning more money goes toward principal reduction as time goes on.

Making extra payments directly reduces the remaining loan principal. Because future monthly interest is computed on a smaller balance, paying extra lowers lifetime interest charges and accelerates your debt payoff date.

The interest rate represents the direct annual cost of borrowing money. The Annual Percentage Rate (APR) reflects the broader cost, including the interest rate plus any mandatory lender origination fees, closing costs, or administrative charges.

This tool is built specifically for calculating loan payments, interest, and amortization schedules. If you need to work with percentages instead, check out CalcNova's Percentage Increase Calculator, Percentage Decrease Calculator, or Reverse Percentage Calculator , all free, fast, and built with the same instant, step-by-step approach as this loan calculator."

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