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Social Security

Free Social Security retirement calculator

A Social Security calculator shows how your benefit — and when you claim it — reshapes your retirement. Because Social Security is guaranteed, inflation-adjusted income for life, every dollar of it is a dollar your portfolio doesn't have to supply. Coastline folds your benefit into a full tax-aware projection, so you see its real effect on what you can spend, not just an isolated benefit estimate.

+$24,000 / year you can spend with $25,000 of Social Security
On a $1,000,000 portfolio at 67, a $25,000/yr benefit lifts sustainable after-tax spending from about $50,500 to $74,500 — Social Security is doing a large share of the work, so the portfolio lasts on a smaller draw.

How Social Security raises your spending

Sustainable after-tax spending on a $1,000,000 portfolio at 67, by annual Social Security benefit (6% nominal return, 3% inflation):

Annual Social Security → sustainable total spending
Social Security / yrPer monthTotal safe spend / yrvs no benefit
None$0$50,500
$15,000$1,250$64,500+$14,000
$25,000$2,083$74,500+$24,000
$35,000$2,917$84,000+$33,500

The claiming decision is worth real money

The calculator's other job is timing. You can claim as early as 62 or as late as 70, and the difference is large and permanent:

Why Coastline's version is different

Most free calculators hand you a single headline number with the assumptions hidden. Coastline is built the opposite way:

This models the benefit's effect on portfolio spending; it isn't an official SSA benefit estimate (get that from your ssa.gov statement). Your real benefit, spouse's benefit, and claiming age change the picture — enter them in the calculator.

Run this with your real numbers
Enter your benefit and claiming age to see how Social Security changes your safe spending and the best time to claim.
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Common questions

What does a Social Security calculator do?

It shows how your benefit and claiming age affect your retirement. Coastline goes beyond an isolated benefit estimate — it folds Social Security into a full tax-aware projection so you see the effect on what you can actually spend.

How much does Social Security raise what I can spend?

Substantially — every dollar of benefit is a dollar you don’t withdraw. In this example, $25,000/yr of Social Security raises sustainable spending on a $1,000,000 portfolio by about $24,000/year.

When should I claim Social Security?

Claiming ranges from 62 to 70. Delaying past full retirement age adds roughly 8% per year to a lifelong, inflation-adjusted benefit, which works as longevity insurance; claiming early starts income sooner but locks in a smaller check. The right choice depends on your health, other income, and whether you’re still working.

Is this an official benefit estimate?

No — for your exact benefit, use your statement at ssa.gov. Coastline uses the benefit you enter to model its effect on your spending and portfolio, and it’s free with no signup.

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