Loan Calculator

A loan calculator turns three numbers — the amount you borrow, the interest rate, and the repayment term — into your monthly payment, total interest, and total cost. Enter your details above and the calculator applies the standard amortization formula instantly.

Step by step

1. Enter the loan amount — how much you want to borrow, e.g. $200,000.
2. Enter the annual interest rate — e.g. 6%. This is the nominal rate, not APR.
3. Enter the loan term in years — e.g. 30 for a 30-year loan.
4. Optional: add a start date to see the exact payoff date.
5. Click Calculate to see your monthly payment, total interest, and a yearly breakdown.

What you get

• Monthly payment — principal and interest, excluding taxes and insurance
• Total interest — what the loan costs you beyond the amount borrowed
• Total of payments — principal plus interest over the full term
• Yearly amortization table — interest vs principal paid each year
• Payoff date — when the loan ends, if you entered a start date

Monthly payments on an amortizing loan are calculated with this formula:

M = P × r(1+r)ⁿ ÷ ((1+r)ⁿ − 1)

• M = monthly payment
• P = principal (loan amount)
• r = monthly interest rate (annual rate ÷ 12 ÷ 100)
• n = number of monthly payments (years × 12)

Worked example

For a $200,000 loan at 6% annual interest over 30 years:

1. r = 6 ÷ 12 ÷ 100 = 0.005
2. n = 30 × 12 = 360
3. M = 200,000 × 0.005(1.005)³⁶⁰ ÷ ((1.005)³⁶⁰ − 1)
4. M = 200,000 × 0.0059955 ÷ 5.0226 = $1,199.10

Total paid = $1,199.10 × 360 = $431,676.38. Total interest = $431,676.38 − $200,000 = $231,676.38.

Interest works the same way in reverse when your money grows: our compound interest calculator shows how compounding builds savings over time.

Amortization means each monthly payment is split between interest and principal. Early on, most of your payment goes to interest because the balance is high. As the balance shrinks, more of each payment attacks the principal. The payment amount never changes — only the split does.

Year-by-year breakdown ($200,000 at 6%, 30 years)

Year	Interest paid	Principal paid	Balance
1	$11,933	$2,456	$197,544
2	$11,783	$2,607	$194,937
3	$11,623	$2,766	$192,171
4	$11,454	$2,936	$189,235
5	$11,274	$3,116	$186,119
...	...	...	...
30	$418	$13,971	$0

In year 1, about 83% of your payments go to interest. In the final year, nearly all of it goes to principal. This front-loaded interest is why extra payments early in the loan save so much.

A shorter term means higher monthly payments but dramatically less total interest. Here is the same $200,000 loan at 6% with different terms:

Term	Monthly payment	Total interest	Total cost
15 years	$1,687.71	$103,788	$303,788
20 years	$1,432.86	$143,887	$343,887
30 years	$1,199.10	$231,676	$431,676

The 30-year payment is about 29% lower than the 15-year payment, but you pay more than twice the interest. Choose the shortest term whose payment fits your budget comfortably. If you are borrowing for a home specifically, our mortgage calculator adds taxes, insurance, and PMI to the picture.

1. Choose a shorter term. A 15-year loan at the same rate saves over $100,000 in interest on a $200,000 loan compared with 30 years.
2. Make extra principal payments. Even $100 extra per month early in the loan cuts years off the term because it directly reduces the balance that interest accrues on.
3. Make biweekly half-payments. Paying half the monthly amount every two weeks equals 26 half-payments a year — one extra full payment annually.
4. Refinance when rates drop. If rates fall 1% or more below your current rate and you plan to stay, refinancing can save thousands. Watch out for closing costs.
5. Avoid extending the term to lower payments. Refinancing into a new 30-year loan restarts the amortization clock, putting you back in the high-interest early years.

According to the Consumer Financial Protection Bureau, understanding how amortization front-loads interest helps borrowers compare the true cost of loan offers beyond the monthly payment.