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Retirement shortfall calculator

The gap between plan and target.

Built and reviewed by Dovanic, Founder and editor, FreeByteLast reviewed: 2026-08-18
$
$
$
6%

Surplus

$3,388

Extra needed monthly

$0

With these inputs, surplus comes to $3,388 over 20 years. The result assumes return stays at 6%.

Projected pot
$1,203,388
Target
$1,200,000

Over time · by years

What moves the number · Surplus

Input−10%Now+10%
Target pot$123,388$3,388$116,612
Current pot$66,126$3,388$72,902
Monthly contribution$47,437$3,388$54,212
Return$109,489$3,388$129,262
Years$157,191$3,388$184,386

Solve for an input

Whatmakesequal

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The gap between plan and target.

A worked example

Starting figures

Target pot
$1,200,000
Current pot
$210,000
Monthly contribution
$1,100
Return
6%
Years
20

What it returns

Surplus
$3,388
Extra needed monthly
$0
Projected pot
$1,203,388
Target
$1,200,000

How to read the results

With the defaults above, surplus works out at $3,388.

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