Income-Driven Repayment Calculator

Estimate your monthly payment under an income-driven repayment plan, based on your income, family size, and loan balance.

Heads up: repayment plan rules changed on July 1, 2026 under the One Big Beautiful Bill Act. Loans disbursed on or after that date use a narrower set of plans (mainly the new Repayment Assistance Plan). Confirm your options with the official Loan Simulator at StudentAid.gov.
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Your most recent AGI (from your tax return)

You, your spouse, and your dependents

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Auto-filled from family size (2025 HHS guidelines, 48 states). Adjust for Alaska, Hawaii, or a newer guideline year.

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Your Estimated Payment

The Discretionary Income Formula

Most income-driven plans use the same core calculation:

Discretionary Income = AGI − (150% × Poverty Guideline)

Then your monthly payment is a percentage of that figure, divided by 12:

  • 10% of discretionary income — new IBR, PAYE, SAVE (graduate)
  • 15% of discretionary income — older IBR
  • 5% of discretionary income — SAVE (undergraduate loans only)

If your AGI is below 150% of the poverty guideline, your discretionary income is zero — and your required payment may be $0.

Why Family Size Matters So Much

Because the poverty guideline rises with family size, a larger family means a higher protected income floor and a lower discretionary income — and therefore a lower payment. Two borrowers with the same $55,000 salary can have very different IDR payments if one supports a family of five and the other files single.

The Standard-Plan Cap

Most IDR plans cap your payment at what you would owe under a standard 10-year repayment plan. So if your income rises sharply, your IDR payment will not exceed the standard amount — it is a ceiling, not a floor.

What Changed in 2026

The One Big Beautiful Bill Act took effect on July 1, 2026. Key changes:

  • Loans disbursed on or after July 1, 2026 use a narrower set of plans, with the new Repayment Assistance Plan (RAP) as the main income-based option.
  • RAP calculates payments as a scaled percentage of AGI (not discretionary income), with a minimum $10 payment and forgiveness after 30 years.
  • SAVE is being wound down, with the plan phased out by July 1, 2028.
  • Borrowers with older loans generally keep access to their existing plans.

Because these rules are still settling, treat this calculator as an estimate and confirm your actual options with the official Loan Simulator at StudentAid.gov.

Low Payment vs. Paying It Off

A low IDR payment is not automatically good. A smaller payment means more interest accrues, so your balance can grow even while you pay. That is a problem if you intend to repay in full — but it works in your favor if you expect forgiveness (PSLF or long-term IDR forgiveness), because the forgiven amount grows while your payments stay small.

See our PSLF calculator and repayment plan comparison to weigh both paths.

Frequently Asked Questions

How is an income-driven repayment payment calculated?

Most income-driven plans base your payment on "discretionary income," which is your adjusted gross income minus 150% of the federal poverty guideline for your family size. Your monthly payment is then a percentage of that figure — typically 10% or 15%, depending on the plan.

What is discretionary income for student loans?

Discretionary income = your AGI − (150% of the poverty guideline for your family size). If your income is below that threshold, your discretionary income is zero and your required payment may be $0. Note that the new Repayment Assistance Plan (RAP) instead uses a percentage of your AGI.

Can my IDR payment be $0?

Yes. If your income is low enough that your discretionary income is zero, your calculated payment can be $0. A $0 payment still counts as a qualifying payment for forgiveness purposes as long as you are enrolled in the plan and meet the other requirements.

Is my IDR payment capped?

Under most income-driven plans, your payment is capped at what you would pay under a standard 10-year repayment plan. That means no matter how high your income rises, your IDR payment will not exceed the standard plan amount.

Did income-driven repayment plans change in 2026?

Yes. The One Big Beautiful Bill Act took effect on July 1, 2026. Borrowers whose loans were disbursed on or after that date have a narrower set of income-driven options, with the new Repayment Assistance Plan (RAP) as the main income-based plan, and existing plans such as SAVE are being phased out by July 1, 2028. Borrowers with older loans generally keep access to their existing plans.

Should I choose the lowest possible payment?

Not always. A lower payment means more interest accrues and a longer path to payoff — unless you expect forgiveness. If you are pursuing Public Service Loan Forgiveness or long-term IDR forgiveness, a lower payment usually works in your favor. If you plan to repay in full, a higher payment saves interest.

Last updated: September 2026 · Reviewed by ScholarPay editorial team · General information only — not tax or financial advice.