Jackpot Calculator is an independent website that estimates what lottery winners actually keep after federal, state and local taxes, for both the lump sum and the annuity.
It is not affiliated with Powerball, Mega Millions, the Multi-State Lottery Association or any state lottery, and it does not sell tickets or link to ticket sellers.
Who runs it
Jackpot Calculator is built and run by Jacky Jian, an independent developer who builds small web tools alongside a day job. Jacky is on X as @jackyjiankn.
Jacky is not a tax professional, so instead of asking you to trust personal expertise, every figure points to a source you can check yourself. Federal rules and verified withholding rates link to government or lottery sources. Most state brackets come from the Tax Foundation compilation; New York, Ohio, Georgia, Illinois, Michigan and Virginia have linked primary rate sources. Published winner payouts check withholding, not the winner’s final tax return. When a figure could not be confirmed on an official page, the site says so rather than guessing.
Corrections
If a number is wrong, we want to know. Use “Report an error” under any result, or email us with a link to the official figure. We check every report against the source. When a figure turns out to be wrong, we fix it as soon as we have confirmed the correct one and list the change, with its date, in the corrections log. We do not change numbers without recording it.
How often the numbers are updated
- Jackpots: Powerball and Mega Millions jackpots and cash values are checked three times a day against the estimates published by the New York Lottery, and the site is rebuilt when they change. Each page shows which drawing its figures are for and when the estimate was published.
- Winning numbers: Millionaire for Life results are added each day from New York State's open data.
- Tax rates: federal and state rates are checked when each new tax year begins and reviewed every three months for changes made during the year, such as Georgia's 2026 rate cut. The methodology shows when the tax data was last checked.
What the site covers
Jackpot Calculator launched on October 1, 2026. It covers federal income tax, the income tax of all 50 states and Washington, D.C., and city tax in New York City and Yonkers. Lottery withholding has been confirmed from an official source for 35 of the 46 jurisdictions that sell Powerball, and 11 published payouts are used as withholding checks, within $1 for exact figures or the stated press-release rounding tolerance. The methodology lists the formulas, sources, assumptions and every known limitation.
Funding and independence
The site may show advertising from Google AdSense. Ads are chosen by Google, are labeled “Advertisement”, and never change the calculations or the order of any results. The privacy policy explains how advertising cookies work and how to turn off personalized ads.
We do not accept payment for links, placements or coverage, and we do not publish sponsored content. Advertisers, lotteries and ticket sellers have no say in what we publish and do not review pages before they go live.
Contact
Email hello@jackpotcalculator.com. If you think a number is wrong, include a link to the official figure — see the contact page. Journalists can find current figures to quote on the press page.