Student Loan Calculator: Standard vs Extended Plans

What this calculator covers, and what changed

This calculator compares the fixed-payment federal plans: the classic 10-year Standard plan, the 25-year Extended fixed plan, and the new Tiered Standard plan. It also works for private loans, which are nearly always fixed payments over a set term.

Federal repayment rules shifted a lot in 2025 and 2026. The One Big Beautiful Bill Act created two plans for loans made on or after July 1, 2026: a Tiered Standard plan with a term set by how much you owe, and the Repayment Assistance Plan (RAP), an income-driven plan. The SAVE plan is being shut down, and older income-driven plans are being phased out for existing borrowers. Income-driven payments depend on your income and family size, not just your balance, so they aren't modeled here. Use Loan Simulator on StudentAid.gov for those, and treat anything you read about IDR from before mid-2025 as possibly outdated.

The formula

Every fixed plan uses the same amortization formula: payment = P × r(1 + r)^n ÷ ((1 + r)^n − 1), where P is your balance, r is the annual rate divided by 12, and n is the number of months (120 for 10 years, 300 for 25). Federal Direct Loans use simple daily interest, which works out to the same thing when you pay on time every month.

If you have several loans at different rates, enter the total balance and a weighted average rate: multiply each balance by its rate, add those up, and divide by the total balance. That's also how a Direct Consolidation Loan sets its rate, rounded up to the nearest eighth of a point.

Worked example: $38,000 at 6.5%

Standard 10-year plan: $431.48 a month, $13,778 in total interest.

Extended fixed 25-year plan (you qualify because you owe more than $30,000 in Direct Loans): $256.58 a month, but $38,974 in interest. You save $174.90 a month and pay $25,196 more over the life of the loan. The interest ends up larger than the original balance.

Tiered Standard: $38,000 falls in the $25,000 to $49,999 tier, so the term is 15 years. That's $331.02 a month and $21,584 in interest, a middle ground.

Add $100 a month on top of the standard payment and the loan is gone in about 7 years and 7 months, with about $10,200 in interest instead of $13,778.

How the Tiered Standard terms work

For new loans from July 1, 2026, the term depends on your total balance when you enter repayment: under $25,000 gets 10 years, $25,000 to $49,999 gets 15, $50,000 to $99,999 gets 20, and $100,000 or more gets 25. The payment is fixed for the whole term. Confirm your assigned term with your servicer, because the balance counted can include loans you already had.

Choosing a plan

If you can afford the 10-year standard payment, it's the cheapest fixed option by a wide margin. Longer terms are a cash flow tool, not a savings strategy. A good middle path: pick the longer term for the lower required payment, then pay extra whenever you can. Federal loans have no prepayment penalty, and extra money goes to interest first, then principal.

If you work in public service, don't pick a plan by payment alone. Public Service Loan Forgiveness requires 120 qualifying payments under a qualifying plan, and payments under the Extended plan generally don't count. Check PSLF eligibility before you switch.

If money is tight, look at the income-driven option before you stretch to 25 years or stop paying. A missed federal payment turns into delinquency after one day and can be reported to credit bureaus after 90 days.

Mistakes that make student loans cost more

Letting unsubsidized interest capitalize. Interest that builds during school or deferment can be added to your principal, and then you pay interest on the interest. Paying the interest while in school keeps the balance flat.

Refinancing federal loans into private ones without thinking it through. You might get a lower rate, but you permanently lose federal protections: income-driven plans, deferment, forbearance, and any future forgiveness.

Skipping autopay. Most federal servicers and many private lenders cut your rate by 0.25 points for automatic payments. It's free money.