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Student Loan Calculator

Ready to calculate
Standard Amortization.
20+ Currencies.
Year-by-Year Payoff.
100% Free.
No Data Stored.

How it Works

01Loan Balance

Your current remaining principal balance

02Remaining Term

Years and months left until full payoff

03Interest Rate

Your weighted-average rate across all student loans

04See Payoff Plan

Monthly payment, total interest, year-by-year schedule

What is a Student Loan Calculator?

The Student Loan Calculator computes your monthly payment, total interest, and year-by-year payoff schedule for any fixed-rate student loan — federal or private. Enter your current loan balance, remaining term (years + months), and interest rate; the calculator returns the exact level monthly payment using the standard amortization formula M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1], alongside the total amount you'll pay across the life of the loan and the total interest cost.

Most federal student loans default to the Standard 10-year repayment plan — a fixed monthly payment designed to pay off the balance in 120 months. Private student loans typically use similar fixed-rate amortization with terms ranging from 5 to 20 years. This calculator handles any fixed-rate scenario: set the balance, term, and rate, and see exactly what the math produces — no surprises, no hidden assumptions.

Built for borrowers with active student loans, recent graduates planning repayment, financial aid counselors, dietitians and guidance counselors at schools, loan-servicer customer teams, and anyone evaluating refinancing options. Free, fast, mobile-friendly, fully client-side — nothing leaves your browser.

Pro Tip: Even an extra $50–$100 per month toward principal can shave years off your payoff and save thousands in interest. This calculator's year-by-year table shows you exactly how the balance shrinks.

How to Use the Student Loan Calculator?

Enter Your Current Loan Balance: Your remaining principal — not the original loan amount. Use the number your servicer shows today.
Enter the Remaining Term: Years and months left until full payoff. Federal Standard plan defaults to 10 years. Private loans vary 5–20.
Enter the Interest Rate: Your current annual interest rate. If you have multiple loans at different rates, use the weighted-average rate across all balances.
Press Calculate: The tool runs the amortization formula and shows your level monthly payment, total cost, and full payoff schedule.
Review the Year-by-Year Table: See how much principal and interest you pay each year, and your remaining balance at the end of each year — useful for goal-setting and payoff tracking.

How do I calculate student loan payments?

Student loan amortization uses the same level-payment formula as mortgages and personal loans: M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1], where P is the remaining balance, r is the monthly interest rate (annual / 12 / 100), and n is the total number of monthly payments left.

The key twist for student loans: in early payments, most of the money goes toward interest, not principal. This is why paying extra toward principal in the first few years of the loan saves disproportionately more interest than paying extra later.

Student Loan Math — Step by Step:

1. Monthly Interest Rate

Annual APR → monthly rate:

  • r = annual rate / 12 / 100
  • 6.8% APR (typical federal) → r = 0.00567
  • Per-month ~0.567%

Federal undergrad Direct Subsidized/Unsubsidized fixed at the year's Treasury rate + spread.

2. Total Months Remaining

Term in months:

  • n = years × 12 + months
  • Standard plan: 10 years = 120 months
  • Extended plan: up to 25 years

Repayment term affects monthly payment dramatically.

3. Apply the Formula

Level monthly payment:

  • M = P × r(1+r)ⁿ / [(1+r)ⁿ − 1]
  • Same amount every month
  • Shrinks principal faster each month

Example: $30,000 @ 6.8%, 120 mo → M ≈ $345.24.

4. Total Cost of Loan

Multiply payment by months:

  • Total paid = M × n
  • Total interest = total − principal
  • Interest can exceed 30% of principal over 10 yrs

Example continues: $41,429 total, $11,429 interest (38% of principal).

US Federal Student Loan Rates (Recent Years):

Direct Subsidized & Unsubsidized (Undergrad)

5 – 8% APR

Tied to the 10-year Treasury rate + 2.05% spread. Capped at 8.25%.

Direct Unsubsidized (Graduate)

7 – 9% APR

Treasury + 3.60%. Higher than undergrad rates.

Direct PLUS (Grad / Parent)

8 – 10% APR

Treasury + 4.60%. Used for remaining cost of attendance after other aid.

Federal Repayment Plan Options:

Standard (10 years)

Fixed payment

Default federal plan. Level payments over 120 months. This calculator models this plan exactly.

Graduated

Starts low, rises

Payments start low and increase every 2 years. Useful for expected income growth. This calculator doesn't model graduated — use standard as a proxy.

Extended (up to 25 years)

Long term

Stretches repayment across 25 years. Lower monthly payment, much more total interest. Requires $30K+ balance.

Income-Driven (IBR/PAYE/REPAYE/SAVE)

% of discretionary income

Payment = 5–20% of discretionary income. Remaining balance forgiven after 20–25 years. Different math — use studentaid.gov's official simulator.

Real-World Example

Student Loan — Real Scenarios

How student loan balances, rates, and terms translate to real monthly payments (USD):

Scenario Balance Rate Term Monthly Total Interest
Typical undergrad$30,0006.8%10 yrs$345$11,429
Same @ 5 years$30,0006.8%5 yrs$591$5,453
Extended plan$30,0006.8%25 yrs$208$32,477
Grad school balance$80,0008%10 yrs$971$36,467
Private refinance (good credit)$50,0005%10 yrs$530$13,639
Small recent grad$15,0005.5%10 yrs$163$4,548

Compare rows 1 and 3: extending from 10 to 25 years drops the monthly payment from $345 to $208, but triples the total interest from $11,429 to $32,477. That's why the Standard 10-year plan is usually the cheapest path to payoff — if you can afford it.

Who Should Use the Student Loan Calculator?

1
🎓 Recent Graduates: Plan your repayment the moment your grace period ends. Know exactly what you owe monthly.
2
💸 Borrowers Considering Refinancing: Compare your current federal loan math against potential private refinance rates. Shorter terms + lower rates = massive savings.
3
🏫 Financial Aid Offices & Guidance Counselors: Patient-facing tool to show families the real cost of student debt before taking on more.
4
📊 Personal Finance Coaches: Run "what if I pay extra" scenarios with clients to motivate accelerated payoff.
5
📈 Graduate / Professional School Decisions: Model debt loads from grad school and the monthly payment they'll create after graduation.
6
🎯 PSLF / Forgiveness Planners: Compare Standard repayment totals against IDR + forgiveness strategies to find the best path.

Technical Reference

Key Takeaways

Student loans are often the largest debt a young adult carries. Use the ToolsACE Student Loan Calculator to quantify exactly what you owe month-to-month and over the life of the loan, year-by-year. The level monthly payment from the amortization formula is the baseline — from there, extra payments toward principal, refinancing at lower rates, and avoiding deferment (interest accrues even during deferment on unsubsidized loans) are the key levers to save money. For Income-Driven Repayment and federal forgiveness programs, use the official studentaid.gov simulators — those follow different rules than the standard fixed-rate math this tool models.

Frequently Asked Questions

What is the Student Loan Calculator?
The Student Loan Calculator computes your monthly payment, total interest, and year-by-year payoff schedule for fixed-rate student loans — federal Direct loans on Standard or Extended repayment plans, or private student loans with any amortization term. It uses the standard amortization formula M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]. Inputs are the current loan balance (in any of 20+ currencies), remaining term (years + months), and annual interest rate.

Outputs: level monthly payment, total paid over the life of the loan, total interest, principal-vs-interest split visualization, and a year-by-year table showing principal paid, interest paid, and remaining balance each year. This is the same math that servicers like Nelnet, MOHELA, and private lenders use for Standard-plan loans.

Note: this calculator does NOT model Income-Driven Repayment (IBR/PAYE/REPAYE/SAVE), which use a different formula based on discretionary income. For IDR modeling, use studentaid.gov's official loan simulator.

How do I calculate my student loan payment?
Use the amortization formula: M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1], where P is your current loan balance, r is the monthly interest rate (annual ÷ 12 ÷ 100), and n is the total number of monthly payments remaining. Example: $30,000 balance at 6.8% APR over 10 years → M ≈ $345.24. This calculator handles the math automatically.
What's the difference between federal and private student loans?
Federal loans (Direct Subsidized, Unsubsidized, PLUS, Consolidation) have fixed rates set annually by Congress, flexible repayment plans (Standard, Graduated, Extended, IDR), and forgiveness options (PSLF, teacher loan forgiveness). Private loans (Sallie Mae, SoFi, Discover, banks) have rates based on your credit profile, fewer repayment options, no federal forgiveness programs, but may offer lower rates for borrowers with excellent credit. This calculator works for both since the underlying math is the same.
What is the Standard repayment plan?
The default federal repayment plan: fixed monthly payments over 120 months (10 years). Designed to pay off the loan completely by the end of the term. Usually results in the lowest total interest cost of any plan. If you don't actively choose a different plan, you're automatically on Standard. This calculator models Standard repayment exactly.
Should I pay extra toward my student loans?
For most borrowers, yes — but with caveats. Extra payments toward principal shrink the balance and save interest. Federal borrowers pursuing PSLF or IDR forgiveness should NOT pay extra, since forgiveness is based on remaining balance after 10/20/25 years. For others (private loans, Standard plan, higher-income earners): pay the minimum on low-rate debts first, then redirect extra cash to higher-rate loans. A $100/month extra payment on a $30K loan at 6.8% can save 2+ years and $3,000+ in interest.
Is refinancing worth it?
Potentially, if you have good credit and high-rate loans. Refinancing private loans into a lower-rate private loan almost always saves money. Refinancing federal loans into private loans is riskier — you lose access to IDR, PSLF, deferment, and forbearance protections. Only consider it if you have stable high income, won't qualify for PSLF, and the rate savings exceed the value of federal protections. Use this calculator to model both rates and compare total costs.
What's Income-Driven Repayment?
IDR plans (IBR, PAYE, REPAYE, SAVE) cap your monthly payment at 5–20% of discretionary income instead of a fixed amortization payment. After 20–25 years of on-time IDR payments, remaining balance is forgiven. The math is completely different from Standard amortization — payments can be $0 for low-income borrowers. For accurate IDR projections, use studentaid.gov's official loan simulator; this calculator models only Standard/fixed-rate amortization.
What's PSLF (Public Service Loan Forgiveness)?
A federal program that forgives the remaining balance of Direct loans after 120 qualifying monthly payments (10 years) while working full-time for a qualifying public service employer (government, 501(c)(3) nonprofits, etc.). Best pursued with an IDR plan (to minimize payments) rather than Standard repayment. Requires careful paperwork — submit the PSLF Employment Certification Form annually.
What happens to interest during deferment or forbearance?
Subsidized federal loans: interest doesn't accrue during deferment. Unsubsidized federal loans and all private loans: interest continues to accrue. When you return to repayment, the accumulated interest capitalizes (adds to principal) — meaning you'll pay interest on interest. Deferment/forbearance should be a last resort; IDR plans often let you keep making $0 payments without capitalization.
How does interest capitalization work?
When unpaid interest is added to the principal balance — usually at the end of deferment, forbearance, or when exiting certain IDR plans. Example: $30,000 loan accrues $2,000 of unpaid interest during a year of forbearance. Post-forbearance, the loan is now $32,000, and you'll pay interest on $32,000 going forward. Avoid capitalization events when possible.
Can I use this calculator for loans in other countries?
Yes. The amortization formula is universal. The calculator supports 20+ currencies including UK Pound, Euro, Canadian Dollar, Indian Rupee, etc. Any fixed-rate student loan following standard amortization works — UK student loans using Plan 1, 2, 4, or 5 use different income-contingent math and aren't modeled here.
Does this calculator track interest that's already accrued but not yet capitalized?
No — it starts from your current loan balance and projects forward. If you have unpaid accrued interest, add it to your balance input for a more accurate estimate (or wait until it capitalizes and use the post-capitalization balance). For precise servicer-matching projections, always verify against your servicer's payoff quote.
Is my financial data private?
All calculations happen locally in your browser. Nothing is sent to a server, saved, or logged. Your loan balance, rate, and term stay on your device. The tool is free and requires no sign-up.

Author Spotlight

The ToolsACE Team - ToolsACE.io Team

The ToolsACE Team

Our finance tools team implements standard fixed-rate amortization for student loans — the same math used by federal Direct loan servicers and private lenders. Works for both federal and private student loans on the Standard 10-year repayment plan and equivalent fixed-rate schedules.

Student Loan AmortizationFederal & Private Loan MathSoftware Engineering Team

Disclaimer

This calculator provides estimates for fixed-rate standard amortization. Federal Income-Driven Repayment (IBR/PAYE/REPAYE/SAVE), consolidation, and forgiveness programs follow different formulas — for those, use official studentaid.gov loan simulators.