Expected Family Contribution (EFC) Estimator
The Student Aid Index (SAI) — formerly called Expected Family Contribution (EFC) — is the number FAFSA calculates to determine your federal financial aid eligibility. A lower SAI means more need-based aid. Understanding the formula lets you make timing and planning decisions that legitimately reduce your SAI before filing. This estimator uses the federal methodology from the Higher Education Act to compute your SAI and show you which factors have the largest impact.
income $10,276 + assets $4,800
income $0 + assets $400
Simplified rule: SAI at or below $0. Real Pell eligibility also depends on Cost of Attendance, which this estimate does not model — many positive-SAI students still qualify for partial Pell.
+$5,000 of parent AGI changes the estimated SAI by $2,350.
View the TypeScript implementation on GitHub: packages/calc/src/efc-calculator.ts · view tests
What this means
The Student Aid Index is the single number the federal formula produces to answer one question: how much can this family be expected to put toward college this year? Colleges then compute need as Cost of Attendance minus SAI and build an aid package up to that gap. A lower SAI means more room for need-based aid. Under the FAFSA Simplification Act the SAI can even go negative — floored at −$1,500 — to distinguish degrees of extreme need.
In my experience, the most useful thing this estimator does is split the number into its parts: parent income, parent assets, student income, student assets. Once you see that the parent income schedule is doing most of the work — and that assets are assessed at a far lower rate — the planning levers become obvious. I’ve found that families anchor on the wrong line: they fret over a $5,000 savings account while a $5,000 swing in base-year income moves the SAI far more.
I want to be blunt about precision, because this is finance-adjacent and the stakes are real: this is a simplified estimate, not your official SAI. It implements the major drivers of the published 2024-25 methodology and deliberately omits refinements (the employment-expense allowance, state aid, the CSS Profile, Cost-of-Attendance-based Pell bands). The authoritative figure comes from filing the FAFSA at studentaid.gov. Use this to understand the shape of the formula and plan — not as the final word.
Worked example
Take the default preset: a dependent student, family of four, with $90,000 parent AGI, $9,000 of federal income tax paid, $40,000 in parent assets, and the student holding $4,000 of income and $2,000 of assets. The family-size-4 income-protection allowance for 2024-25 is $44,530.
Parent Adjusted Available Income is $90,000 − $9,000 − $44,530 = $36,470. Running that through the progressive schedule — 22% on the first $17,000, then 25% / 29% / 34% / 40% across the middle bands, and 47% on the top $2,070 — gives a parent income contribution of $10,276. Parent assets add 12% of $40,000 = $4,800, for a parent contribution of $15,076.
On the student side, $4,000 of income is below the $9,410 allowance, so it contributes $0; $2,000 of assets at 20% adds $400. Total estimated SAI is $15,076 + $400 = $15,476— above the simplified Pell threshold, so this family would not be Pell-eligible on these numbers. Remember: this is an estimate. The official figure comes from the FAFSA at studentaid.gov.
Frequently asked questions
The information and tools on this website are for general educational purposes only and do not constitute financial, investment, legal, or tax advice. Consult a licensed professional for decisions specific to your situation.