Plan smarter.
Pay off your mortgage sooner.

Smart Mortgage Planner is a fast, free mortgage planning tool for Australia. Plan today and enjoy tomorrow by comparing repayments, offset savings, extra payments, lump sums, interest saved, and payoff goals.

See your payoff date
Save thousands
Stay on track
Current loan balance
stat term
Interest rate0.000%
stat frequency
Amortization period
stat payment
Repayment frequency
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Repayment
stat term

Mortgage calculator

Enter your loan details to estimate payoff timing.

Day / Month / Year
$
%

Strategy options

Choose one or more options to compare strategies.

Grow offset account

Offset is linked to the loan and reduces interest charged.

$
$

Extra payment

Add an extra repayment weekly, fortnightly, monthly, or yearly.

$

One-off lump sum

A single payment toward the home loan.

$

Monthly repayment breakdown

Based on the strategy options currently selected.

After selected strategy
Monthly repayment after strategy
This month to interest After offset and lump sum are applied.
This month to principal The part reducing your loan balance.
Interest saved this month Compared with no strategy.

Interest comparison

See how each strategy performs on its own, then compare it with the live combined result from the options you select.

Clear side-by-side comparison
No strategy baseline

This is the estimated interest you would pay if you kept the loan as-is, with no offset, no extra repayments, and no lump sum.

Offset account only Based on your offset balance and offset growth.
Interest you pay
Interest you save

Shows how much interest is reduced by keeping money in offset against the loan.

Extra repayment only Based on the extra repayment amount and frequency.
Interest you pay
Interest you save

Shows the interest saving from paying extra on top of the normal repayment.

One-off lump sum only Based on a single lump sum payment made now.
Interest you pay
Interest you save

Shows the interest saving from putting one single payment into the loan. If the lump sum is $0, the saving will be $0.

All selected strategies

This combines the strategy options currently turned on in the calculator.

Live combined result
Interest you pay
Interest you save
Payoff time
New payoff date

Mortgage balance over time

No strategyOffset onlyAll selected strategies
Payoff time (no strategy)
Payoff time (offset only)
Payoff time (all selected)
Time saved

Payoff goal

Set your target payoff time and see the extra repayment needed.

Goal calculator
years
Extra repayment needed $0 Complete the details to calculate this.
Total repayment target $0 Complete the details to calculate this.
Interest saved $0 Compared with no strategy.
Interest you pay $0 Estimated total interest with this goal.
Estimated payoff date
Smart Mortgage Planner

Plan smarter with one simple mortgage calculator

Smart Mortgage Planner helps homeowners plan today and enjoy tomorrow by estimating how different repayment choices may affect their loan. Enter your balance, interest rate, amortization period, repayment frequency, offset balance, extra repayments, and lump sum payments to compare the estimated interest you pay and the interest you save.

Offset account calculator

Estimate how money kept in an offset or redraw account may reduce interest charged on your mortgage balance.

Extra repayment calculator

See the possible impact of weekly, fortnightly, monthly, or yearly extra repayments on your total interest and payoff time.

Lump sum calculator

Compare the estimated saving from making a one-off payment toward the loan principal.

Payoff goal calculator

Set a target such as paying off your mortgage in 6 years and estimate the extra repayment needed to reach that goal.

Helpful answers

Mortgage calculator FAQ

Quick answers for people comparing mortgage repayment strategies.

What does this mortgage calculator show?

It estimates repayments, interest paid, interest saved, payoff time, and the result of combining offset, extra repayment, and lump sum strategies.

Can I compare different strategies?

Yes. You can compare the no-strategy baseline, offset only, extra repayments only, lump sum only, and all selected strategies together.

Is this financial advice?

No. It is an educational estimate. Actual results can change because of interest-rate changes, lender fees, repayment rules, redraw rules, and offset account conditions.