Medicare Calculators & Tools
Seventeen free calculators for eligibility, costs, IRMAA, plan comparisons, enrollment timing, savings programs, and coverage before you turn 65, using official CMS and Medicare.gov data.
Medicare has four parts, several enrollment windows with penalties for missing them, and a market of private plans on top of the public program. Most questions come down to three things: whether you are enrolled correctly and on time, what it will cost, and which route fits you, Original Medicare with a Medigap policy or a Medicare Advantage plan.
Am I Eligible, and Am I Enrolling on Time?
Most people become eligible at 65, but being eligible is not the same as being enrolled on time. If you miss your Initial Enrollment Period, the seven months around your 65th birthday, you can owe a late enrollment penalty that is added to your premium for as long as you have the coverage. If you are still working and have employer coverage, you may be able to delay without a penalty, depending on the size of the employer and the type of plan. Start with the Medicare Eligibility Checker and the Enrollment Period Finder to confirm your windows, and use the Late Enrollment Penalty Calculator if you think you have missed one. If you already have Medicare, the AEP Countdown shows how many days are left to change plans this year.
Original Medicare vs. Medicare Advantage vs. Medigap
Original Medicare (Parts A and B) is run by the federal government and accepted by any provider in the country that takes Medicare. It has gaps: no yearly limit on out-of-pocket costs, 20% coinsurance on most Part B services, and no routine dental, vision or hearing coverage. People fill those gaps in one of two ways. The first is a private Medigap (Medicare Supplement) policy alongside Original Medicare. The second is a Medicare Advantage (Part C) plan, which adds extra benefits and usually drug coverage but uses a provider network. You cannot have both. Our Medicare Advantage vs Original Medicare comparison and Medigap Plan Comparison Tool set out the trade-offs side by side.
What Will This Cost?
Premiums, deductibles and coinsurance change every year. Higher earners also pay IRMAA, a surcharge on Part B and Part D based on income from two years earlier. It rises in steps, so one dollar over a threshold brings the full surcharge for that tier. The Medicare Cost Calculator and IRMAA Calculator use current official figures to estimate your premium. If you take several prescriptions, the Part D Coverage Gap Calculator shows when you would reach the yearly out-of-pocket cap, and the Part D Plan Comparison Guide explains how drug plans differ before you shop. If you are considering a Roth conversion, the Roth Conversion IRMAA Planner shows whether it would move you into a higher IRMAA tier.
Help If Money Is Tight
Medicare has programs for people with limited income and resources, and many who qualify never apply. Medicare Savings Programs (QMB, SLMB and QI) can pay the Part B premium and sometimes deductibles and coinsurance. Extra Help (the Low-Income Subsidy) lowers Part D drug costs. Check both with the Medicare Savings Program Eligibility Calculator and the Extra Help Eligibility Calculator. If you also qualify for Medicaid, the PACE Program Eligibility Checker and our Prescription Savings Finder cover more sources of help.
Not Yet on Medicare? The Coverage Gap Before 65
If you retire or lose employer coverage before 65, you need health insurance until Medicare starts, and that comes from a different system. The ACA Subsidy Calculator estimates your Marketplace premium tax credit for those years, including the income cutoff for subsidies that returned in 2026. Your income in those years affects how much help you get, so check it before you decide when to retire or claim Social Security.
Every Medicare Tool
Medicare Guides
Health Insurance Before Medicare: How ACA Subsidies Work From 62 to 64
Retiring before 65? How Marketplace subsidies work for 2027, the 400% income cliff, why all of your Social Security counts, and how to switch to Medicare.
Read more → MedicareBest Prescription Drug Plans for Seniors on Medicare
No Medicare drug plan is best for everyone. How to compare Part D plans for your own medications: formulary tier, pharmacy, yearly cost and the caps.
Read more → MedicareDoes Medicare Cover Dental?
Original Medicare does not cover cleanings, fillings, dentures or implants. The medical exceptions, Medicare Advantage dental benefits and lower-cost options.
Read more → MedicareDoes Medicare Cover Ozempic?
Medicare Part D covers Ozempic for type 2 diabetes but not for weight loss alone. What you pay in 2026 and 2027, prior authorization and the GLP-1 Bridge.
Read more → MedicareDoes Medicare Cover Zepbound?
Medicare Part D does not cover Zepbound for weight loss alone. It may cover it for sleep apnea, and the GLP-1 Bridge covers the KwikPen at $50 a month.
Read more → MedicareDoes Medicare Pay for Weight-Loss Surgery?
Medicare covers gastric bypass, lap-band and some other bariatric surgeries for people with a BMI of 35 or more, a related condition and prior failed treatment.
Read more → MedicareDual-Eligible D-SNP Plans: What the New Enrollment Rules Actually Mean
Who can join a D-SNP, the three integration levels, and how plan switching works in 2026 now that the quarterly SEP for dual eligibles is gone.
Read more → MedicareHow Much Does Medicare Cost at Age 65?
What Medicare costs at 65 in 2026: Part A is usually $0, Part B is $202.90 a month, plus a drug plan and supplemental coverage. Surcharges and budgets.
Read more → MedicareThe Medicare 100-Day Rule: Myth vs. Reality
Medicare covers up to 100 skilled nursing days only after a 3-day inpatient hospital stay. Days 1 to 20 are free, and days 21 to 100 cost $217 a day in 2026.
Read more → MedicareMedicare Annual Enrollment Period 2026: What's Actually Different This Year
Medicare open enrollment runs Oct 15 to Dec 7, 2026 for 2027 coverage. What you can change, the 2027 premium and drug cost figures, and how to check your plan.
Read more → MedicareMedicare Appeals, ABNs, and Fast Appeals: How to Fight a Denial
How Medicare appeals work: the ABN warning before a service, the five appeal levels and their deadlines, and the fast appeal when a hospital stay is ending.
Read more → MedicareDoes Medicare Cover Durable Medical Equipment? The Supplier Rule Nobody Explains
Medicare Part B pays 80% for wheelchairs, walkers, CPAP and other equipment, but only through a Medicare-enrolled supplier. Renting and buying explained.
Read more → MedicareMedicare Enrollment Periods Explained: IEP, GEP & the SEP Trap
Medicare's Initial, Special and General Enrollment Periods explained, and why COBRA and retiree coverage do not extend the 8-month window for Part B.
Read more → MedicareWhat Is the Medicare "Grocery Card"? How the OTC Benefit Actually Works
There is no government Medicare grocery card. Some Medicare Advantage plans offer an OTC or grocery allowance to their own members. What it covers.
Read more → MedicareThe Medicare Part B Giveback: How It Works and Who Qualifies
A Part B giveback is a Medicare Advantage plan benefit that lowers your Part B premium. Who qualifies, how it shows up in your check, and what to compare.
Read more → MedicareThe Medicare Prescription Payment Plan (M3P) Explained
The Medicare Prescription Payment Plan spreads your Part D drug costs into monthly bills. It does not lower what you owe. Who it helps and who should skip it.
Read more → MedicareMedicare Special Needs Plans: How C-SNPs and I-SNPs Work
Who qualifies for a Medicare Special Needs Plan, the conditions C-SNPs cover in 2026, how I-SNPs work for nursing home residents, and when you can join.
Read more → MedicareMedigap Plan G vs Plan N: The Real Difference Isn't the Copays
Medigap Plan G and Plan N differ in two ways: Plan N has small office and ER copays, and it does not cover Part B excess charges. The cost math.
Read more → MedicareDoes Medicare Cover Hearing Aids? What Is Covered, What Is Not, and Other Ways to Pay
Original Medicare does not cover hearing aids, but Part B covers hearing exams and implants. Medicare Advantage, OTC hearing aids, Medicaid, VA and tax options.
Read more → MedicareDoes Medicare Cover Glasses and Eye Exams? What Vision Care Medicare Pays For
Medicare skips routine eye exams and glasses, but covers glasses after cataract surgery plus glaucoma, diabetic eye and macular degeneration care.
Read more →Browse all Medicare guides → Dental, vision and hearing guides →
Frequently Asked Questions
What's the difference between Original Medicare and Medicare Advantage?
Original Medicare (Part A and Part B) is run directly by the federal government and lets you see any provider that accepts Medicare nationwide. Medicare Advantage (Part C) is a private-plan alternative that usually bundles in Part D drug coverage and extra benefits, but typically uses a network and requires referrals.
What happens if I miss my Initial Enrollment Period?
You may owe a late enrollment penalty that is added to your Part B or Part D premium for as long as you have the coverage, and you may have to wait for the next General Enrollment Period to sign up. The exception is a Special Enrollment Period, most often because you had coverage through an employer.
Do I need a Medigap plan if I have Original Medicare?
Not required, but Original Medicare alone leaves you responsible for deductibles, coinsurance, and 20% of most Part B costs with no annual cap. A Medigap policy covers some or most of that gap. It cannot be paired with Medicare Advantage.
What is IRMAA and who has to pay it?
IRMAA (Income-Related Monthly Adjustment Amount) is a surcharge added to Part B and Part D premiums for higher-income beneficiaries, based on your tax return from two years prior. Most beneficiaries never hit the income threshold and pay the standard premium.
This page is for general educational purposes and is not affiliated with Medicare.gov or CMS. The figures in our calculators come from official CMS publications. See our Data Sources page for details.