FreeByte

Overpay or save calculator

Where a spare payment works hardest.

Built and reviewed by Dovanic, Founder and editor, FreeByteLast reviewed: 2026-08-18
$
6.5%
4.5%

Overpay the debt

$5,162 better

Value either way

$50,521

With these inputs, overpay the debt comes to $5,162 better over 10 years. Value either way works out to $50,521. The result assumes debt rate stays at 6.5%.

Overpaying is worth
$50,521
Saving is worth
$45,359

Over time · by years

What moves the number · Overpay the debt

Input−10%Now+10%
Spare monthly amount$4,645 better$5,162 better$5,678 better
Debt rate$3,406 better$5,162 better$6,997 better
Savings rate$6,229 better$5,162 better$4,061 better
Years$4,020 better$5,162 better$6,495 better

Solve for an input

Whatmakesequal

Compare scenarios

Save this set of inputs, change something, then save again to compare the outcomes side by side.

Where a spare payment works hardest.

A worked example

Starting figures

Spare monthly amount
$300
Debt rate
6.5%
Savings rate
4.5%
Years
10

What it returns

Overpay the debt
$5,162 better
Value either way
$50,521
Overpaying is worth
$50,521
Saving is worth
$45,359

How to read the results

With the defaults above, overpay the debt works out at $5,162 better.

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