PlanMath

Free calculators for health benefits decisions

No login, no lead form, no sales pitch. Enter your numbers, get a straight answer. Built by someone who works in healthcare benefits administration for a living.

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HSA vs FSA

Compare real after-tax savings between the two, including the forfeiture risk an FSA carries that an HSA doesn't.

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Job loss

COBRA cost estimator

See what COBRA actually costs once your employer stops covering their share, not just the 2% fee everyone talks about.

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Choosing a plan

Plan cost comparison

Compare two plans by total real cost, premium plus out-of-pocket, based on how much care you actually expect to use.

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Covering a family

Family deductible calculator

See what each person pays, what the household pays, and when the family caps kick in. Embedded or aggregate, side by side.

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Medicare enrollment

Part B & D penalty calculator

These penalties are permanent, not one-time. See what a missed enrollment window actually costs over the years.

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Job or life change

Mid-year plan switch calculator

A lower premium looks good on paper until your deductible resets to zero. See the real remaining-year cost before switching.

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Medicare, higher income

IRMAA surcharge calculator

Your income from two years ago decides what you pay today. See your bracket and how close you are to the next one.

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Why this exists

Most health benefits decisions get made with incomplete numbers, a premium here, a deductible there, no clear total. These tools do the actual math in one place, using the same logic that decides real claims. Nothing here is tax, legal, or insurance advice, and each calculator says exactly what it doesn't account for. Confirm specifics with your plan administrator before making a final decision.