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Installment True APR Calculator

Finance & Investment

IRR-based true annualized rate of installment plans

Quick Answer

Installment True APR Calculator: IRR-based true annualized rate of installment plans. Cash-flow equation: payment A = P·i ÷ (1 − (1+i)^(−n)), solved by bisection.

Installment fees are charged on the FULL principal every period while your balance shrinks — the true APR is roughly 2× the nominal fee rate.

True annualized rate (IRR)

13.84%
Monthly payment1,072.00
Total fees864.00
Nominal total rate7.20%
Approx APR13.29%

Step-by-step

  1. 1Fee per period: 12,000 × 0.6% = 72.00; principal per period: 1,000.00
  2. 2Monthly payment: 1,072.00 × 12 periods = 12,864.00 total
  3. 3Nominal total fee rate: 0.6% × 12 = 7.20%
  4. 4Approx APR (rule of thumb): 24 × 0.6 × 12 / (12+1) = 13.29%
  5. 5Exact IRR: monthly 1.0862% → annualized (1+i)^12 − 1 = 13.84%

Quick lookup: fee rate → true APR (%)

Fee/period3 mo6 mo12 mo24 mo
0.3%5.5%6.3%6.8%7.0%
0.5%9.4%10.7%11.5%11.7%
0.6%11.3%12.9%13.8%14.1%
0.75%14.3%16.4%17.5%17.7%

💡 Watch for wording: "0 interest, only handling fee" still has a real APR. Early payoff usually does NOT refund remaining fees. Regulators require lenders to disclose the annualized (IRR) rate — always compare that number.

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How to Use

  1. Enter amounts and terms: fill principal, rate and period in the Installment True APR Calculator (defaults work for a quick try).
  2. Instant results: key figures and cost breakdown update live as you type.
  3. Compare scenarios: tweak any parameter to compare costs and returns across plans.
  4. Copy key numbers: one-click copy for records or sharing with your advisor.

Key Points

  • Installment True APR Calculator is a free online finance tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: IRR-based true annualized rate of installment plans.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

True APR of installments (IRR)

Cash-flow equation: payment A = P·i ÷ (1 − (1+i)^(−n)), solved by bisection
Nominal APR = i×12; effective annual rate = (1+i)¹² − 1
Advertised "fee rate" = (nA − P) ÷ P — far below the true rate

Example: ¥12,000 over 12 months at ¥1,072/mo: nominal 7.2% but true APR ≈ 13.0%.

FAQ

How do I use the Installment True APR Calculator?
Open the page and fill in the input fields — results update automatically. IRR-based true annualized rate of installment plans.
Are the results accurate?
Yes. Standard financial formulas and published rate data are used. For official figures, consult your financial institution.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required.
Can I use the results for financial decisions?
Results are for reference. Consult a licensed financial advisor before major decisions.
Does it work on mobile?
Yes. Fully responsive on phones, tablets and desktops.

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Source & Updates

Based on published rate tables and standard financial formulas. Last updated: 2025-07

Authoritative sources:

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Installment True APR Calculator[EB/OL]. https://www.yijiansuan.com/en/c/finance/installment-rate

Results provided by this tool are for reference only and do not constitute professional advice.