How the calculator works

The calculator runs in your browser and sends nothing anywhere. It projects each plan month by month from today: it works out the payment, applies it to interest and then principal, and repeats until the loan is paid off, forgiven, or reaches the end of the plan.

The inputs it uses

• Loans. Each loan’s type, balance and rate. Direct and FFEL/Perkins loans are combined into one balance at their balance-weighted average rate. Parent PLUS and private loans are handled separately (below).
• Loan dates. Whether you owed a federal loan before July 1, 2014 (which sets IBR at 15% instead of 10%) and whether any loan was made on or after July 1, 2026 (which limits you to RAP and Tiered Standard).
• Income and household. AGI, filing status, your spouse’s AGI and federal loan balance if you file jointly, household size (for IBR’s poverty line), dependents (for RAP) and state (Alaska and Hawaii have their own poverty guidelines).
• Work. Employer type, PSLF payments already counted, and whether you work full time.
• The starting example. The calculator opens with one Direct Loan of $38,000 at 6.39% and an AGI of $55,000 so the results aren’t blank. 6.39% is the fixed rate on undergraduate Direct Loans first paid out from July 1, 2025 to June 30, 2026 (91 FR 10084, March 2, 2026). The balance and income are an illustration, not an average. Replace all three with your own.
• Two assumptions you can change. Income grows 3% a year and the poverty guideline grows 2.5% a year unless you set something else. Both apply once every 12 months.

Repayment Assistance Plan

Source: Higher Education Act section 455(q), added by Public Law 119-21 (July 4, 2025), and 34 CFR 685.209 as amended effective July 1, 2026.

1. Base payment: $120 a year if AGI is $10,000 or less; otherwise 1% of AGI for $10,001 to $20,000, rising one point per $10,000 band to 9% for $90,001 to $100,000, and 10% above $100,000. The percentage applies to the whole AGI.
2. Monthly payment = base ÷ 12 − $50 for each dependent.
3. If you file jointly and your spouse has eligible loans, multiply by your share of the couple’s combined eligible balance (34 CFR 685.209(g)(3)).
4. If the result is under $10, the payment is $10. The last payment can be smaller.
5. Each month, interest your payment doesn’t cover is not charged. If the payment reduced principal by less than $50, principal is reduced further so the month’s total principal reduction equals the smaller of $50 and your payment.
6. Any balance left after 360 payments is shown as forgiven.

Income-Based Repayment

Source: Higher Education Act section 493C as amended by Public Law 119-21, and 34 CFR 685.209.

1. Discretionary income = AGI (joint AGI if you file jointly) − 150% of the HHS poverty guideline for your household size and state. 2026 guidelines: $15,960 for one person plus $5,680 per extra person in the 48 states and D.C.; $19,950 plus $7,100 in Alaska; $18,360 plus $6,530 in Hawaii.
2. Payment = 10% of discretionary income ÷ 12 if you had no federal loan balance before July 1, 2014, otherwise 15%.
3. Joint filers whose spouse has eligible loans: multiplied by your share of the couple’s balance.
4. Then, under $5 becomes $0; $5 to under $10 becomes $10.
5. The payment never exceeds the 10-year Standard payment. The law fixes that cap on your balance when you first enter IBR; the calculator uses your balance today.
6. Forgiveness after 20 years (10% borrowers) or 25 years (15% borrowers).
7. IBR is shown as unavailable if any loan was made on or after July 1, 2026.

Standard and Tiered Standard

• 10-year Standard (loans made before July 1, 2026 only): a level payment that pays the balance off in 120 months, at least $50.
• Tiered Standard (only if a loan was made on or after July 1, 2026): a level payment over 10 years if your total principal (including any Parent PLUS loans) is under $25,000, 15 years for $25,000 to under $50,000, 20 years for $50,000 to under $100,000, and 25 years for $100,000 or more, at least $50 (34 CFR 685.208).

PSLF

Shown when you choose a government or 501(c)(3) employer and full-time work. The calculator runs RAP and, if it’s open to you, IBR for the payments you have left out of 120, then shows the balance at that point as forgiven, tax free. It doesn’t model the 10-year Standard plan for PSLF because that plan pays the loan off at payment 120 anyway, and it never counts Tiered Standard, which doesn’t qualify.

Parent PLUS and private loans

Parent PLUS loans can’t use RAP, so they get their own box: the 10-year Standard payment, and an IBR estimate (15% of income above 150% of the poverty line; 10% if you had no federal loan balance on July 1, 2014) that applies only if the loan is a consolidation made before July 1, 2026 and you make one ICR payment before ICR ends. If you have a loan made on or after July 1, 2026, Parent PLUS loans are shown on Tiered Standard, the only plan the law allows them then.

Private loans are used only in the refinancing comparison.

Refinancing

You type an APR you’ve been offered and a term. The calculator shows the level payment and total for that loan and compares it with your cheapest federal plan, assuming any private loans would otherwise run 10 years at their current rate. If PSLF is in reach, it says refinancing would end it instead of recommending a refinance. It never shows lender rates of its own.

What it leaves out

These make real payments differ from the projection:

• Interest capitalization under IBR and Standard when you leave a plan or end a deferment. The calculator never capitalizes.
• Missed recertification. Under RAP, missing it sets your payment to the 10-year Standard amount until you send your income.
• Income changes other than steady growth: job changes, marriage, children, years off.
• Individual loans. Combining loans at a weighted rate is close for level payments but not exact when rates differ widely.
• Payment counts you already have toward IBR or RAP forgiveness. The forgiveness dates assume you start at zero, except for PSLF, where you enter your count.
• Taxes. Forgiveness under RAP or IBR after 2025 can be taxable as income; studentaid.gov says it “could create a federal tax liability.” The calculator doesn’t estimate that tax.
• The autopay discount. Studentaid.gov’s IDR court actions page (updated September 29, 2026) says the autopay rate reduction on Direct Loans disbursed on or after July 1, 2012 rose from 0.25% to 1% on July 1, 2026, as a temporary benefit through June 30, 2028, for borrowers enrolled by 11:59 p.m. Eastern on December 31, 2026. Enter your rate after the discount if you have it.
• ICR, PAYE, Graduated and Extended plans. ICR and PAYE close by July 1, 2028; Graduated and Extended are available to borrowers whose loans all predate July 1, 2026 and can be checked with your servicer or the Loan Simulator on studentaid.gov.

When the rules change

Every number above lives in one file in the site’s code, next to its source. When Congress, the Department or a court changes a rule, that file and this page change together, and the date at the top moves.