What is the monthly payment on 100,000 at 5% for 30 years?

About 536.82 a month with level payments, and about 93,256 in total interest. With equal principal, payments start at 694.44 and fall each month.

Which costs less interest, level payment or equal principal?

Equal principal, because the principal is repaid sooner, although the early payments are larger. The "Compare repayment types" table shows the total interest of all three.

What is the formula for a monthly loan payment?

Payment = loan × monthly rate ÷ (1 − (1 + monthly rate)^−months), with the monthly rate equal to the annual rate ÷ 12.

How do I calculate interest on an interest-only loan?

Each month's interest is loan × annual rate ÷ 12, and the whole principal is repaid with the last payment. On 100,000 at 5 % that is 416.67 a month.

How much interest will I pay on a 30,000 loan over 5 years?

It depends on the rate. At an assumed 6 %, level payments are 579.98 a month with about 4,799 in total interest; equal principal brings it to 4,575.

Does an interest-only period increase the total interest?

For level-payment and equal-principal loans, yes. The balance does not fall during that period, so interest keeps building, and with the same term the later payments are higher.

Can I download the amortization schedule to Excel?

Yes. Press "Save as CSV" next to "Repayment schedule" for a file with payment number, principal, interest, payment and balance that opens directly in Excel.

Does it calculate early repayment fees?

No. Early repayment terms and fees differ by product and contract, so they are not included; check them with your lender.

Can I enter the loan term in months?

Yes. Choose "Months" under "Term in" to calculate terms such as 18 months that are not whole years.

Does it work with a 0% interest rate?

Yes. Interest is then zero, and both level payment and equal principal repay the loan amount ÷ the number of months each month.

Loan Calculator — payment and interest

Monthly payment and total interest for a mortgage or personal loan. Compare level payment, equal principal and interest-only, and save the amortization schedule

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A loan calculator that shows the monthly payment and total interest for three repayment types at once: level payment, equal principal and interest-only. Use it before a mortgage or personal loan to see what you will pay each month and how much the repayment type changes the total interest. It compares all three in one table, handles an interest-only period at the start, and gives a full amortization schedule of principal, interest and balance that you can save as CSV.

How to use

Enter the amount you will borrow under "Loan amount" and the agreed rate in percent under "Annual interest rate". Change "Currency" if needed.
Enter the "Loan term" and choose "Years" or "Months" under "Term in".
If you pay only interest for the first few months, enter them under "Interest-only period". These months count within the loan term.
Choose "Level payment", "Equal principal" or "Interest-only" under "Repayment type" to see the "Monthly payment" ("First payment" for equal principal), "Total interest" and "Total repaid".
Use the "Compare repayment types" table to see the first and last payment and total interest of all three side by side, and the "Balance and interest paid so far" chart to see how the balance falls.
Open a year in the "Repayment schedule" to see principal, interest and balance for each payment, and press "Save as CSV" for a file that opens in Excel or Google Sheets.

How it works

The monthly rate is the annual rate ÷ 12; 5 % a year is about 0.4167 % a month.
Amounts are rounded only for display, so a lender's figures may differ by a cent or so per payment.
The interest-only period does not apply to the interest-only repayment type, which pays only interest until the whole principal is repaid in the last month.
Rate changes, early repayment and its fees, day-count rules from the start date, insurance and other charges are not included. These depend on the product and contract, so check them with the lender.
Everything you enter is calculated in this browser on this device and is not sent anywhere.

Level payment vs equal principal vs interest-only (200,000 at 6.5% for 30 years)

Borrow 200,000 at 6.5 % a year for 30 years (360 months). With level payments you pay 1,264.14 every month and about 255,089 in interest overall. With equal principal you repay 555.56 of principal each month plus interest on the remaining balance, so payments start at 1,638.89 and fall to 558.56, with about 195,542 in total interest. Interest-only costs 1,083.33 a month, then the full 200,000 is due with the last payment, and the interest adds up to 390,000.

Equal principal costs the least interest and interest-only the most, because the sooner the principal is repaid, the sooner the balance that earns interest shrinks. The catch is that equal principal is heaviest at the start. People who want a steady payment usually choose level payments; those who can afford more early on and want less total interest often choose equal principal. Interest-only keeps the monthly cost lowest but needs the whole principal at the end.

Monthly loan payment formula and how the first month's interest is worked out

The level payment is loan × monthly rate ÷ (1 − (1 + monthly rate)^−months). For 100,000 at 5 % over 360 months, the monthly rate is 0.05 ÷ 12 ≈ 0.004167 and the formula gives 536.82. This calculator uses the same formula.

Each month's interest is the balance at the start of that month × the monthly rate. The first month's interest on 100,000 is about 416.67, so only 120.15 of the first 536.82 payment goes to principal. That is why a level-payment balance falls slowly at first: after a year about 98,525 is still owed, against about 96,667 with equal principal.

How much extra interest does an interest-only period cost?

During an interest-only period you pay interest but no principal. For 100,000 at 5 % over 30 years with 12 interest-only months, the first 12 payments are 416.67 each, then level payments of 544.86 for the remaining 348 months. That is about 8 more a month than without the period (536.82), and total interest rises to about 94,611, roughly 1,356 more.

With equal principal and the same 12 months, total interest is about 77,708, some 2,500 more than without them. The balance does not fall during the interest-only months, so interest keeps building, and the principal has to be repaid over fewer months within the same term.

Why a loan calculator can differ from your lender's figures

This calculator applies the annual rate ÷ 12 every month. Many real loans charge interest by the day from the date the money is paid out to the first due date, so the first payment can differ, and lenders round in different ways.

A variable-rate loan is repriced when the reference rate changes, so a 30-year total worked out at today's rate only holds if that rate never changes. Rates, borrowing limits and early repayment fees depend on law and on each product and are not part of this calculator, so compare the result with the repayment plan your lender gives you before signing.

Questions and answers

What is the monthly payment on 100,000 at 5% for 30 years?: About 536.82 a month with level payments, and about 93,256 in total interest. With equal principal, payments start at 694.44 and fall each month.
Which costs less interest, level payment or equal principal?: Equal principal, because the principal is repaid sooner, although the early payments are larger. The "Compare repayment types" table shows the total interest of all three.
What is the formula for a monthly loan payment?: Payment = loan × monthly rate ÷ (1 − (1 + monthly rate)^−months), with the monthly rate equal to the annual rate ÷ 12.
How do I calculate interest on an interest-only loan?: Each month's interest is loan × annual rate ÷ 12, and the whole principal is repaid with the last payment. On 100,000 at 5 % that is 416.67 a month.
How much interest will I pay on a 30,000 loan over 5 years?: It depends on the rate. At an assumed 6 %, level payments are 579.98 a month with about 4,799 in total interest; equal principal brings it to 4,575.
Does an interest-only period increase the total interest?: For level-payment and equal-principal loans, yes. The balance does not fall during that period, so interest keeps building, and with the same term the later payments are higher.
Can I download the amortization schedule to Excel?: Yes. Press "Save as CSV" next to "Repayment schedule" for a file with payment number, principal, interest, payment and balance that opens directly in Excel.
Does it calculate early repayment fees?: No. Early repayment terms and fees differ by product and contract, so they are not included; check them with your lender.
Can I enter the loan term in months?: Yes. Choose "Months" under "Term in" to calculate terms such as 18 months that are not whole years.
Does it work with a 0% interest rate?: Yes. Interest is then zero, and both level payment and equal principal repay the loan amount ÷ the number of months each month.