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Personal Loan Calculator

Calculate monthly payments, total interest, and true APR for any personal loan. Supports origination fees to show the real cost of borrowing.

Calculation Inputs

Results computed instantly — your data never leaves your device.

Live Results

Real-Time

Monthly Payment

$494.64

Total Interest

$2,807.04

18.7% of principal

Total Cost

$17,807.04

Interest Rate

11.50%

Nominal annual rate

Net Proceeds

$15,000

Amount deposited to your account

100% Client-SidePrivate & Secure

Amortization Snapshots

MonthPaymentPrincipalInterestBalance
1$494.64$350.89$143.75$14,649.11
12$494.64$389.7$104.94$10,560.14
24$494.64$436.96$57.68$5,581.9
36$494.64$489.94$4.7$0

How to Use the Personal Loan Calculator

  1. 1

    Enter the loan amount you wish to borrow and the annual interest rate quoted by your lender.

  2. 2

    Set the loan term in months (e.g. 36 for 3 years, 60 for 5 years). Your monthly payment and total interest update instantly.

  3. 3

    Toggle "Include Origination Fee" if your lender charges one, and enter the fee as a dollar amount or percentage — the calculator adjusts your true APR automatically.

  4. 4

    Review the amortization table to see exactly how much of each payment goes to principal vs interest, and track your remaining balance month by month.

Formula & Mathematical Basis

Monthly payment: M = P × r × (1 + r)^n ───────────────────── (1 + r)^n − 1 True APR (Newton-Raphson on cash flows): Solve for i such that: Net Proceeds = Σ [ M / (1 + i)^t ] for t = 1 to n where Net Proceeds = P − Origination Fee APR = i × 12

Variable Key

P

Principal — full loan amount before any fees are deducted

r

Monthly interest rate = Annual Rate ÷ 12 ÷ 100

n

Loan term in months

M

Fixed monthly payment (principal + interest)

i

True monthly cost rate used to derive APR, solved iteratively

APR

Annual Percentage Rate — total annualised cost including origination fee

📝 APR estimation uses Newton-Raphson iteration (typically converges in < 20 steps). The result matches the Truth in Lending Act (TILA / Regulation Z) definition used by U.S. lenders. For fee-free loans, APR equals the nominal annual rate exactly.

Step-by-Step Examples

1

Debt consolidation loan — no origination fee

Scenario: $15,000 loan at 9.5% APR, 48-month term, no origination fee.

  1. 1.Monthly rate r = 9.5% / 12 / 100 = 0.7917%.
  2. 2.Monthly payment: $15,000 × 0.007917 × (1.007917)^48 / [(1.007917)^48 − 1] = $375.82.
  3. 3.Total paid: $375.82 × 48 = $18,039.36.
  4. 4.Total interest: $18,039.36 − $15,000 = $3,039.36.
✅ $375.82/month | $3,039 total interest | Effective APR = 9.50%
2

Home improvement loan — 3% origination fee

Scenario: $20,000 loan at 11.0% stated rate, 60-month term, 3% origination fee ($600).

  1. 1.Monthly rate r = 11.0% / 12 / 100 = 0.9167%.
  2. 2.Monthly payment on $20,000: $20,000 × 0.009167 × (1.009167)^60 / [(1.009167)^60 − 1] = $434.85.
  3. 3.Net proceeds received: $20,000 − $600 = $19,400.
  4. 4.True APR via Newton-Raphson on [$19,400 disbursed, 60 × $434.85 repaid]: APR ≈ 12.15%.
  5. 5.Total interest (on stated principal): $434.85 × 60 − $20,000 = $6,091.
✅ $434.85/month | Stated rate 11.0% → True APR ≈ 12.15% | $6,091 total interest

Practical Use Cases

  • ✓ Consolidating high-interest credit card debt into a single fixed monthly payment
  • ✓ Financing home improvements, medical expenses, or major purchases without collateral
  • ✓ Comparing loan offers from multiple lenders using APR as the apples-to-apples metric
  • ✓ Planning monthly budget impact before accepting a loan offer
  • ✓ Understanding the true cost of origination fees vs lower-rate but fee-free alternatives
  • ✓ Evaluating whether a shorter term is affordable given the higher monthly payment

Common Mistakes to Avoid

  • ⚠ Comparing loans by interest rate only — always compare APR, which includes origination and other mandatory fees.
  • ⚠ Borrowing more than needed to cover the origination fee — if possible, pay the fee upfront instead of financing it.
  • ⚠ Choosing the longest term to minimise payments without considering total interest — a 5-year term can cost 60–70% more in interest than a 3-year term.
  • ⚠ Ignoring prepayment penalty clauses — some lenders charge a fee if you pay off the loan early.
  • ⚠ Treating the monthly payment as the full cost — total interest is the actual price of borrowing and should always be reviewed.
  • ⚠ Missing a payment: unsecured personal loans typically carry penalty rates and late fees that substantially increase the effective cost.

Glossary of Terms

Principal
The original loan amount borrowed, before interest. All monthly payments reduce the outstanding principal.
APR (Annual Percentage Rate)
A standardised annual cost that includes interest plus mandatory fees. Required to be disclosed by lenders under TILA (Regulation Z) in the US.
Origination Fee
A one-time lender fee (typically 1–8% of the loan) charged to underwrite and fund the loan. Usually deducted from disbursement, not paid upfront.
Amortisation
The process of paying off a loan in equal periodic instalments, with each payment covering accrued interest first and then reducing principal.
Unsecured Loan
A loan backed only by the borrower's creditworthiness, with no collateral. Personal loans are typically unsecured, which means higher rates than secured alternatives.
Soft vs Hard Credit Pull
A soft pull (pre-qualification) does not affect your credit score; a hard pull (formal application) typically causes a temporary 5–10 point dip.
Debt-to-Income Ratio (DTI)
Total monthly debt payments divided by gross monthly income. Most lenders prefer DTI below 36%; above 43% typically disqualifies applicants.

Frequently Asked Questions

What is the difference between the interest rate and APR on a personal loan?

▾
The interest rate (also called the nominal rate) determines your monthly payment on the principal. APR (Annual Percentage Rate) includes the interest rate plus all mandatory fees — most importantly the origination fee — expressed as a single annualised cost. Because origination fees are typically deducted from your disbursement but you still repay the full loan amount, the APR is always higher than the stated rate. The calculator estimates APR using Newton-Raphson iteration on the true cash-flow sequence.

How is the monthly payment on a personal loan calculated?

▾
Personal loans use standard amortisation: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the principal, r is the monthly rate (annual rate ÷ 12), and n is the number of months. Each month's payment covers first the interest on the remaining balance, then reduces principal — early payments are mostly interest; later payments are mostly principal.

What is an origination fee and how does it affect my loan?

▾
An origination fee (typically 1%–8% of the loan amount) is charged by lenders to process the loan. It is usually deducted from your disbursement — so if you borrow $10,000 with a 3% fee, you receive $9,700 but repay $10,000. This makes your true borrowing cost (APR) meaningfully higher than the quoted interest rate. Always compare loans using APR, not just the interest rate.

Is it better to choose a shorter or longer loan term?

▾
A shorter term means higher monthly payments but significantly less total interest paid. A longer term reduces monthly cash flow pressure but increases total cost substantially. Use the calculator to compare: a $15,000 loan at 12% for 36 months costs ~$2,931 in interest; stretched to 60 months, total interest rises to ~$4,896 — 67% more — for the same loan amount.

Can I pay off a personal loan early?

▾
Most unsecured personal loans allow early payoff with no prepayment penalty, though you should confirm with your lender. Paying extra toward principal reduces the remaining balance and cuts future interest. Even one extra payment per year on a 5-year loan can save hundreds of dollars and several months of repayment.

Sources & References

  1. [1]
    Truth in Lending Act (TILA) — Regulation Z— Consumer Financial Protection Bureau (CFPB), 2024
  2. [2]
    What Is a Personal Loan?— Consumer Financial Protection Bureau (CFPB), 2024
  3. [3]
    Understanding Loan Costs— Federal Reserve (FRB), 2023

CalculatorFree Finance TeamTILA/Regulation Z compliance review

Personal loan APR methodology verified against CFPB Regulation Z requirements and standard amortisation schedules.

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