Student Loan APR Calculator
This calculator compares standard monthly amortization with a bi‑weekly schedule (26 payments per year). It shows periodic payments, total paid, total interest, and the effective annual percentage rate implied by the chosen nominal APR.
Use the tool to estimate savings from more frequent payments and to understand how nominal APR maps to effective annual cost when payment frequency changes.
Compute fixed bi‑weekly payments assuming interest is applied per bi‑weekly period (26 periods per year). This method treats the nominal APR divided by 26 as the period rate.
Inputs
Results
Bi‑weekly payment
$97.82
Total paid
$25,433.77
Total interest
$5,433.77
Effective APR (annual)
512.21%
Number of bi‑weekly payments
260
| Output | Value | Unit |
|---|---|---|
| Bi‑weekly payment | $97.82 | USD |
| Total paid | $25,433.77 | USD |
| Total interest | $5,433.77 | USD |
| Effective APR (annual) | 512.21% | % |
| Number of bi‑weekly payments | 260 | — |
Visualization
Methodology
Calculations assume fixed-rate amortizing loans with interest accrued per payment period. Monthly calculations use 12 periods per year; bi‑weekly calculations use 26 periods per year. Period rate = nominal APR / periods per year.
Effective APR is computed as (1 + period_rate)^(periods_per_year) − 1 and expressed as an annual percent. Where lenders use daily interest accrual or different compounding conventions, results are estimates.
Accuracy and security guidance: numeric accuracy targets follow best practices for reproducible financial computation. Implementation and data handling should follow NIST guidance for secure numerical libraries and ISO/IEC recommendations for numeric data interchange. This tool does not provide legal, tax, or regulatory advice; consult an advisor for compliance-specific questions.
Worked examples
Example 1: $20,000 principal, 5% APR, 10 years. Compare monthly payment vs bi‑weekly payment and see total interest difference.
Example 2: Add a $10 extra payment per bi‑weekly period to see the impact on interest saved and earlier payoff.
Further resources
Expert Q&A
Does the bi‑weekly option always save money?
If bi‑weekly payments increase the number of payments per year (for example paying half of the monthly payment every two weeks results in 13 monthly equivalents), you typically reduce interest and shorten term. Savings depend on how interest is accrued; this calculator assumes per‑period compounding and shows the estimate.
What is the difference between nominal APR and effective APR?
Nominal APR is the stated annual percentage rate. Effective APR reflects compounding for the chosen payment frequency and equals (1 + period_rate)^(periods_per_year) − 1.
Are results exact for every lender?
No. Lenders may use daily accrual, different compounding conventions, fees, or rounding rules. Use these results as close estimates and verify with your loan servicer for exact payoff schedules.
Is extra payment applied to principal immediately?
This calculator treats extra payment as applied at each period in addition to the scheduled payment, reducing principal and interest in subsequent periods. Verify with your servicer how they apply extra payments.
Sources & citations
- NIST Computer Security and Reliability Guidance — https://www.nist.gov
- ISO/IEC Numeric and Financial Data Interchange Standards — https://www.iso.org
- IEEE Recommended Practices for Numerical Software — https://www.ieee.org
- Consumer-facing loan disclosure guidance — https://www.consumerfinance.gov