Loan Calculator

Calculate monthly repayments, total interest and a full amortization schedule.

%
years
Formula: PMT = P · r / (1 − (1 + r)^−n)
  • P = loan principal
  • r = monthly interest rate (annual ÷ 12)
  • n = number of monthly payments

How to use the Loan Calculator

  1. Enter the loan amount. The total amount you're borrowing.
  2. Add rate and term. Your annual interest rate and the length in years.
  3. Review the schedule. See your monthly payment and the year-by-year breakdown.

Why use our Loan Calculator

Full amortization. See exactly how much of each year goes to principal vs interest.
Any loan. Mortgages, car loans, personal loans — any amount, rate and term.
Instant results. Payment and schedule update the moment you change a value.

Free to use — premium coming soon

FREE
  • Monthly payment
  • Total interest
  • Amortization schedule
PREMIUM
  • Remove ads
  • Extra-payment modelling
  • Export schedule to PDF/CSV

About the Loan Calculator

The Loan Calculator turns three numbers you already know into the figures lenders rarely show up front: your fixed monthly repayment, the total interest you will pay over the life of the loan, and a year-by-year breakdown of how the balance falls. Enter the amount you want to borrow, the annual interest rate, and the term in years, and it computes everything instantly. It works for any fixed-rate installment loan with equal payments, whether that is a car loan, a personal loan, a student loan, or a home loan, because the underlying math is the same for all of them.

Reach for this tool before you sign anything. Comparing two offers becomes simple when you can see that a slightly lower rate or a shorter term changes the total interest by hundreds or thousands. It also helps when you are budgeting: knowing the exact monthly figure tells you whether a loan fits alongside your other commitments. Many people use it to test a hypothetical, such as borrowing $20,000 over five years versus seven, and immediately see how stretching the term lowers the monthly payment while raising the total interest paid.

Behind the scenes it uses the standard amortization formula, M = P[r(1+r)^n] / [(1+r)^n - 1], where P is the principal, r is the monthly interest rate (the annual rate divided by 12), and n is the number of monthly payments (years times 12). Each month, interest is charged on the remaining balance, and whatever is left of your fixed payment reduces the principal. Because the balance shrinks every month, the interest portion steadily falls and more of each payment attacks the principal, which is why the amortization schedule shifts so dramatically from the first year to the last.

Everything is calculated in your browser, so the loan amount, rate, and term you type never leave your device or get sent to a server. There is nothing to save and no account to create. One accuracy note: the result assumes a fixed rate and equal monthly payments, and it does not include lender fees, insurance, or taxes. Because of that, the rate you enter behaves like a nominal interest rate rather than an APR, which also folds in fees, so a real quote with charges may cost slightly more than the figure shown here.

Frequently asked questions

How does the calculator work out my monthly payment?

It applies the standard amortization formula, dividing your annual rate by 12 to get a monthly rate and multiplying your term in years by 12 to get the number of payments. This produces one fixed payment that fully clears the loan, principal plus interest, by the final month.

Why does so much of my early payment go to interest?

Interest is charged on the outstanding balance, which is highest at the start. Early on, most of each payment covers that interest and only a little reduces the principal; as the balance falls, the interest portion shrinks and more of each payment goes to principal.

Is the interest rate the same as APR?

No. The rate you enter is the nominal interest rate on the principal. APR also includes fees such as origination charges, so it is usually a bit higher. Use APR when comparing the true cost of two loan offers.

Will paying extra each month really save money?

Yes. Any amount above your scheduled payment goes straight to the principal, reducing the balance interest is charged on and shortening the term. Most installment loans have no prepayment penalty, but it is worth confirming with your lender first.

Does the calculator include taxes, insurance, or fees?

No. It shows only principal and interest for a fixed-rate loan with equal payments. For a mortgage, you would add property taxes, homeowners insurance, and any closing costs separately to see your full monthly outlay.

From our blog

How the Army One-Site Tape Test Works and How to Estimate Your Score

By the Super Simple Digital Tools Team · Updated June 2026

The Army Body Composition Program exists to keep soldiers within a healthy body composition range, and in 2024 it moved to a simpler way of measuring it. Where the old method required taping multiple sites and applying log-based equations, the current one-site test asks for just your body weight and the circumference of your abdomen. That change makes the assessment faster, more consistent between graders, and easy to replicate at home, which is exactly what this calculator does.

The process starts with a screening, not a tape. Each soldier is first checked against a height and weight table for their age and sex. If you fall at or under the maximum screening weight for your height, you meet the standard and no tape test is needed. Only when you exceed that weight does the abdominal measurement come into play to determine your body fat percentage, so knowing your number in advance tells you whether the tape will ever come out.

Taking the measurement correctly matters more than people expect. Use a flexible tape that does not stretch, remove belts and bulky clothing, and stand tall with feet about hip-width apart. Place the tape at the level of your navel, keep it horizontal all the way around, and snug it against the skin without compressing the tissue. Read it at the end of a relaxed breath out. Because a single reading can be off, the Army takes three and averages them to the nearest half inch.

Once you have weight and abdomen in hand, the formula does the rest. Men and women use different equations because body fat distributes differently, but both depend only on those two inputs. Plug your averaged abdomen measurement and current weight into the calculator and it returns an estimated percentage. The tool then compares that figure to the maximum allowed for your age group, giving you a clear pass or work-needed signal rather than just a raw number.

Treat the output as a planning tool. Trends matter more than any one reading: track your estimate every couple of weeks as you train, and you will see how abdominal measurement responds to changes in diet and conditioning. When an official assessment is on the calendar, measure under the same conditions each time so your home estimates stay comparable, and remember that your unit's graded result is the one that counts on the record.

  • Average three abdomen readings to the nearest half inch, just as a grader would, instead of trusting a single measurement.
  • Measure at the navel at the end of a relaxed exhale, and never suck in or push your stomach out.
  • Compare your weight to the height and weight screening table first; if you are under it, the tape test may not apply at all.
  • Re-check your estimate at the same time of day and in similar conditions so progress between sessions is genuinely comparable.

Read the full guide →

Tool by the Super Simple Digital Tools Team. Reviewed by our editorial team. Free to use, no signup required.

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