People type this into search every day: student loan repayment calculator.
The usual answer is the 10-year standard plan. Federal Student Aid’s standard repayment page says that plan uses a fixed monthly payment. For Direct Subsidized, Unsubsidized, and PLUS loans the maximum period is 10 years. Consolidation loans can run longer. That is a plan name. It is not the only payment a servicer will accept.
This page is a labeled example. It is not your servicer’s bill, and it is not personalized financial advice.
A fixed payment clears the balance if it covers the interest
The loan amortization schedule calculator is the tool this post uses for a payoff date. The site used to keep a separate student-loan repayment page. That slug now points here, because the math is the same fixed-payment loop.
Each month the tool adds balance × annual rate ÷ 12 as interest. Then it subtracts the scheduled payment and any extra payment you typed. It repeats until the balance is gone, or until 1,200 months.
The rate stays fixed. Interest compounds monthly. There are no fees, skipped payments, penalties, or new borrowing in this model.
Fig 1
One month on a fixed loan
Interest lands first. The rest of the payment can cut principal.
The scheduled payment is set so the original term hits zero if you never send extra.
Federal loans often accrue interest by the day. The CFPB’s when and how repayment starts note is about grace periods and who you pay, not this monthly loop. Most Direct Loans have a six-month grace period after you leave school or drop below half-time. Interest can still grow in that window. Parent PLUS loans do not get that grace period unless the parent asks to defer.
This calculator is a monthly model. It will not match a daily-interest statement to the penny. Use it to see how term and extra principal move the date.
Income-driven plans are a different machine. The CFPB’s IDR explainer says those payments follow income and family size. The federal repayment options page says an IDR payment can be as low as $0, and that you use the Education Department’s Loan Simulator to pick a plan. This site does not compute IDR. If your payment is set from income, the year count below is the wrong formula.
The published $25,000, 5-year path
Here are the calculator defaults. They are a 5-year fixed loan, not a claim about the average student balance.
- starting loan balance: $25,000
- fixed annual interest rate: 7.2%
- original loan term: 5 years
- extra monthly payment: $100
Scheduled months: 5 × 12 = 60
Monthly rate: 0.072 ÷ 12 = 0.006
Scheduled payment: $497.39
Payment with the $100 extra: $597.39
Estimated payoff: 4y 1m
Total interest: $3,874.83
Balance after year 1: $19,450.53
Calculator result
Loan amortization schedule
- Starting loan balance
- $25,000.00
- Fixed annual interest rate
- 7.2%
- Original loan term
- 5 years
- Extra monthly payment
- $100.00
4y 1m
estimated payoff time
- Scheduled payment
- $497.39
- Payment with extra
- $597.39
- Total interest
- $3,874.83
Month 1 interest is 25000 × 0.006 = $150.00. The $597.39 payment then leaves 597.39 − 150 = $447.39 for principal, so the next balance starts at 25000 − 447.39 = $24,552.61 before the following month’s interest. I am only showing month 1 by hand. The card’s $19,450.53 is the loop after 12 of those months.
Turn the extra payment off and keep $25,000, 7.2%, and 5 years.
Payoff: 5y 0m
Payment: $497.39
Total interest: $4,843.54
Balance after year 1: $20,690.94
The $100 extra saved 4,843.54 − 3,874.83 = $968.71 of interest and 11 months. That is 60 − 49 = 11.
Fig 2 · 1/2
Month 1 of the $497.39 payment
$25,000 at 7.2%. Extra is off in this split.
Interest
$150.00
Principal
$347.39
Interest is $150.00, 30.2% of the first payment.
Principal is $347.39. Later months give principal a larger share.
$150.00 ÷ 497.39 = 30.2%. The leftover 347.39 ÷ 497.39 = 69.8%. Year 1 still ends at $20,690.94 if you send only the scheduled $497.39, because early months carry more interest than late ones.
Stretch the same $25,000 to 10 years
Federal Student Aid’s standard plan is a 10-year fixed payment for those Direct Loan types. Here is that term on the same $25,000 and 7.2%, with extra set to $0.
Scheduled payment: $292.85
Payoff: 10y 0m
Total interest: $10,142.56
Balance after year 1: $23,228.03
Calculator result
Loan amortization schedule
- Original loan term
- 10 years
- Extra monthly payment
- $0.00
10y 0m
estimated payoff time
- Scheduled payment
- $292.85
- Payment with extra
- $292.85
- Total interest
- $10,142.56
The 5-year scheduled payment was $497.39. The 10-year payment is 497.39 − 292.85 = $204.54 lower. Interest rises by 10142.56 − 4843.54 = $5,299.02. You pay the same $25,000 of principal either way.
Total sent on the 5-year path: 497.39 × 60 = $29,843.40, which is principal plus $4,843.54 of interest (two cents sit in rounding on the monthly payment).
Total sent on the 10-year path: 292.85 × 120 = $35,142.00, next to the card’s $10,142.56 of interest.
Fig 3 · 1/2
Same $25,000, two terms
7.2% fixed. Extra payment is $0.
- Principal
- Interest
| Category | Principal | Interest |
|---|---|---|
| 5 years | $25k | $4.8k |
| 10 years | $25k | $10k |
Five years costs $4,843.54 of interest.
Ten years costs $10,142.56 of interest on the same principal.
A longer term shrinks the monthly number and raises the interest pile. That is the same trade the mortgage payment post already walks for a house loan.
A second labeled loan: $35,000 at 6.5% for 10 years
People also search with a rounder balance and a 10-year term. Here is a labeled case, still not a federal average.
- starting balance: $35,000
- rate: 6.5%
- term: 10 years
- extra: $0
Scheduled payment: $397.42
Total interest: $12,690.15
Balance after year 1: $32,430.33
Month 1 interest: 35000 × 0.065 ÷ 12 = $189.58
Month 1 principal: 397.42 − 189.58 = $207.84
Interest is 189.58 ÷ 397.42 = 47.7% of that first payment. The 10-year $25,000 path put only 25000 × 0.072 ÷ 12 = $150.00 of interest in month 1, which was 150 ÷ 292.85 = 51.2% of its smaller payment. A lower rate and a larger balance can still spend about half the first check on interest.
Add $50 extra each month on this $35,000 loan.
Payment with extra: $447.42
Payoff: 8y 7m
Total interest: $10,650.40
Interest saved versus $0 extra: 12690.15 − 10650.40 = $2,039.75
Months saved: 120 − 103 = 17
Add $100 extra instead.
Payment with extra: $497.42
Payoff: 7y 5m
Total interest: $9,186.19
Interest saved: 12690.15 − 9186.19 = $3,503.96
Months saved: 120 − 89 = 31
Fig 4 · 1/3
Interest on the $35,000, 10-year path
6.5% fixed. Labeled example, not a federal average.
- Total interest
| Category | Total interest |
|---|---|
| $0 extra | $13k |
| $50 extra | $11k |
| $100 extra | $9.2k |
The scheduled path costs $12,690.15 of interest.
$100 extra cuts that to $9,186.19 and finishes in 7y 5m.
Fig 5 · 1/2
Remaining balance over 10 years
$35,000 at 6.5%. The extra-$100 path ends in year 8 of this chart.
Remaining principal
- Scheduled
- $100 extra
| Point | Scheduled | $100 extra |
|---|---|---|
| 0y | $35k | $35k |
| 2y | $30k | $27k |
| 4y | $24k | $18k |
| 6y | $17k | $8.0k |
| 8y | $8.9k | $0.00 |
| 10y | $0.00 | $0.00 |
After four years the scheduled balance is still $23,641.86.
With $100 extra the same year is $18,176.86, and year 8 is already $0.
On the scheduled path, year 8 still holds $8,921.47. The extra-$100 path is already at $0 by then, because payoff is 7y 5m.
The CFPB federal repayment page says extra payments, or prepayments, should be applied to principal if you tell the servicer that. This calculator assumes the extra lands on principal every month. If a servicer parks the extra as a prepaid installment, you do not get these months back.
The payment formula is the same one a personal loan uses
The personal loan payment calculator solves the scheduled monthly amount:
P × r(1+r)ⁿ ÷ ((1+r)ⁿ − 1)
That is the standard amortizing payment. Fees in this tool are paid up front, not financed.
Defaults on that card:
- amount borrowed: $15,000
- annual rate: 9.5%
- term: 4 years
- upfront fees: $250
Monthly payment: $376.85
Total interest: $3,088.66
Total cost including fees: $18,338.66
Put the $25,000, 7.2%, 5-year student-loan numbers into this card and set fees to $0.
Monthly payment: $497.39
Total interest: $4,843.54
Total cost: $29,843.54
That $497.39 is the same scheduled payment the amortization tool printed. The two cards share the formula. The amortization card then walks the months and lets you add extra.
The $35,000, 6.5%, 10-year labeled loan on this card is $397.42 a month, $12,690.15 of interest, and $47,690.15 total. Same pair as above.
Extra principal has its own card
The early loan payoff calculator starts from a remaining balance and a remaining term. It builds the scheduled payment, then adds your extra.
Defaults:
- remaining balance: $18,000
- annual rate: 8.5%
- remaining term: 48 months
- extra each month: $100
Scheduled payment: $443.67
Payoff with extra: 38 months
Months saved: 10
Interest saved: $711.10
Calculator result
Early loan payoff
- Remaining balance
- $18,000.00
- Annual interest rate
- 8.5%
- Remaining term
- 48 months
- Extra payment each month
- $100.00
38 months
estimated payoff time
- Months saved
- 10
- Interest saved
- $711.10
- Scheduled payment
- $443.67
Set extra to $0 and the same $18,000 finishes in 48 months, with $0 saved. The $100 is what bought the 10 months and the $711.10.
The $35,000, 6.5%, 120-month labeled loan on this card matches the amortization walk. Extra $50: 103 months, 17 months saved, $2,039.75 of interest saved. Extra $100: 89 months, 31 months saved, $3,503.97 of interest saved. One cent sits between that last figure and the $3,503.96 from subtracting the two amortization interest totals. The two loops rounded separately.
The credit card payoff post is this same monthly interest-then-payment idea on a revolving balance. A student loan in this model does not take new charges. The snowball vs avalanche post is the order you attack several debts. One extra $100 can only land in one place each month.
What a servicer can do that this page cannot
Private student loans follow the contract. The CFPB start-paying note says the lender or servicer should tell you when and how to pay. There is no IDR formula on that side unless the contract writes one.
Federal loans can move onto IDR, graduated repayment, extended repayment, deferment, or forbearance. Those paths change the payment, the term, and sometimes the interest that gets added to principal. The CFPB options page also says a 0.25% rate reduction is available if you enroll in direct debit. I am not going to invent your new payment after that 0.25%. Type the rate you actually have.
Default on most federal loans is 270 days without a payment, per that same CFPB page. This calculator will not warn you about that. It only runs the months you pay.
Open the loan amortization schedule calculator with the balance, the rate on the statement, and the payment you plan to send. Use the personal loan payment calculator when you only need the scheduled monthly amount. Use the early loan payoff calculator when the term is already set and you want the months an extra payment buys. If the loan is federal and the payment is set from income, use the Education Department’s Loan Simulator instead of this loop.