Loan Balance Calculator — Remaining Balance by Date

Last updated: Sep 15, 2025

Inputs

Currency

Principal

APR (%)

Term (years)

+ Months

Start date

Payment frequency

Compounding

Nominal APR converted to payment-period rate using compounding choice.

Day-count convention

Interest-only period (months)

Balloon at end (optional)

Rounding mode

Extra payments

Recurring extra (each payment)

One-time amount

One-time date

You can add multiple one-time extras below.

0 items

As-of options

As-of mode

As-of date

As-of N

No data leaves your browser.

Summary

Remaining balance

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Interest remaining

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Next payment

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Payoff date

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Interest saved

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Balance over time

Principal vs interest (first 60 payments)

Amortization schedule

Filter by year Tip: sort by clicking the column headers (use your browser's table-sort extension if needed).

Each row shows one scheduled payment with any extra amounts applied to principal.
#	Date	Payment	Interest	Principal	Extra	Balance
Totals		—	—	—	—	—

How to calculate remaining loan balance

Enter principal, APR, term, start date, and select your payment frequency.
Optional: add extra payments (recurring or one-time), an interest-only period, and/or a final balloon.
Choose as-of date or number of payments to see your outstanding balance and payoff timeline.
Export the schedule to CSV or PDF, or copy a shareable link.

Assumes a fixed nominal APR. Use day-count modes if your lender accrues interest by days (30/360, ACT/365, ACT/ACT).

FAQ

How accurate is this calculator?

It uses the standard amortization math with optional day-count accrual. Rounding modes let you match lender practices. Always compare with your statement.

Does bi-weekly lower balance faster?

Yes. 26 half-payments a year reduce interest vs 12 monthly payments at the same APR because you effectively pay more frequently.

What if my payment is lower than interest?

You’ll see a negative-amortization warning. The balance would grow until payments increase.

Behind the Calculator: Math Assumptions Methods and Worked Example

This loan balance calculator models a standard fully amortizing installment loan with optional interest only months a final balloon and flexible payment frequencies monthly bi weekly or weekly. The nominal APR you enter is converted into an effective per period rate using your selected compounding method match payments monthly or daily. Each scheduled period accrues interest then applies the scheduled payment plus any extras first to interest and then to principal. When extras exceed what is necessary for the current period the excess reduces principal immediately which shortens the payoff timeline and lowers total interest. If a payment is lower than the interest due the unpaid interest is carried forward and the tool flags negative amortization because the balance would increase rather than fall.

For most users the periodic method is appropriate which applies a constant per period rate. Lenders may also accrue by days using conventions such as 30 360 ACT 365 or ACT ACT. Day count methods matter most when you change payment dates or mix weekly bi weekly and monthly schedules. The calculator includes both families so you can match your lender statement more closely and understand variations from rounding or policy.

Core Symbols and Formulas

Quantity	Symbol	Definition
Principal	PV	Original loan amount
Nominal APR	i	Annual percentage rate as a decimal e.g. 0.065
Payments per year	k	12 monthly 26 bi weekly 52 weekly
Per period rate	r	Derived from i and compounding method r = (1 + i/m)^m/k − 1 when compounding m differs from k
Term in periods	n	Total scheduled payments
Balloon	FV	Target ending balance at term end optional
Payment	PMT	PMT = [ r(PV − FV/(1+r)ⁿ) ] / [ 1 − (1+r)⁻ⁿ ] with r = 0 handled as linear

Day Count Options at a Glance

Method	Annual denominator	Typical usage
30 360	360	Commercial and some mortgages approximates each month as 30 days
ACT 365	365	Consumer lending and credit cards simple and common
ACT ACT	365 or 366	Splits by calendar year more precise over leap years

Worked Example

Suppose PV is 300000 APR is 6.5 percent k is 12 and the term is 30 years with no balloon. The per period rate r is derived from the APR and your compounding choice match payments is the default which converts the nominal APR to an effective rate consistent with twelve payments per year. The payment formula returns a monthly PMT that covers interest and principal. If you add a 100 recurring extra plus a 5000 one time extra after twelve months the schedule immediately reduces principal and the cumulative interest falls. The Summary panel will show interest saved versus the baseline with no extras and a sooner payoff date.

To evaluate a balance on a specific date choose By date under As of options the tool steps through each scheduled period applying day count interest if selected until it finds the last payment on or before that date. The listed balance is the outstanding principal after all payments and extras through that point. Alternatively select After N payments to jump straight to a payment count which is helpful when reconciling against lender histories or exporting reports.

Results may differ slightly from statements because lenders can round per payment or at the end of the schedule treat grace days differently or compound on non standard calendars. Use the rounding selector and day count table to align the model and document any remaining policy gaps in your records.