Loan Student Loan Calculator
Student debt rarely comes as one loan — it arrives as a stack of them, each with its own rate. Add up to five, set one repayment term, and see the combined payment, the total interest, and what an extra payment does across the whole stack.
Each loan’s minimum is the standard amortizing payment for the term you set. Extra money is aimed at the highest-rate loan first (the avalanche order), which is the cheapest way through the stack.
How it works
Every loan gets its own standard payment — balance × monthly rate ÷ (1 − (1 + monthly rate)−term) — and the minimums simply add up. The simulator then walks the stack month by month: minimums everywhere, interest accruing on each balance, and any extra payment aimed at the highest APR first. When a loan dies, its minimum rolls into the extra for the next one, which is why the payoff speeds up toward the end.
Formula & worked example
Formula: Each loan gets the standard amortizing payment for the term — balance × monthly rate ÷ (1 − (1 + monthly rate)−term) — and the minimums add up. Extra money is aimed at the highest APR first (avalanche order); when a loan is cleared, its minimum rolls into the attack on the next.
Worked example: Two loans on a 10-year term: $5,000 at 5% costs $53.03 a month and $7,000 at 6.5% costs $79.48 — a combined $132.52, with $3,901.96 of interest over 120 months. Add $100 a month extra aimed at the 6.5% loan and everything is gone in 60 months, with $1,784.55 of interest: $2,117.41 saved.
Frequently asked questions
How do I find the payment on several student loans?
Work out each loan’s standard payment for your term, then add them. Two loans — $5,000 at 5% and $7,000 at 6.5% — on a 10-year term cost $53.03 + $79.48 = $132.52 a month and $3,901.96 of interest in total. The calculator above does the adding for up to five loans.
Which student loan should extra money hit first?
Mathematically, the highest interest rate — every dollar there removes the most future interest. On the example stack, $100 a month extra aimed at the 6.5% loan clears everything in 60 months instead of 120 and saves $2,117.41 of interest.
Is a 10-year term always right?
It is the federal standard plan, but not a law. A shorter term raises the payment and cuts interest hard; a longer term does the opposite and can cost more than the original degree expenses you financed. Model two or three terms above and compare the total interest line, not just the monthly one.
Should I pay extra on federal student loans?
Only after weighing what you give up: income-driven repayment, Public Service Loan Forgiveness and hardship deferment are worth real money. If none of those plausibly apply to you, extra payments are a guaranteed return equal to the loan’s APR.
🧮 More than student debt?
The Debt Snowball Calculator lines up six debts of any kind and races the snowball against the avalanche.