Not in a browser. Not in the cloud. On your machine — your accounts, your numbers, free to explore with no account needed to start. ZBee brings your investment accounts together and shows how much you can safely spend in the years ahead, all on your own Mac.
Free to explore on realistic sample data — connecting your own accounts arrives with ZBee Pro, coming soon.
Built for Apple silicon (M1 and later) · Free to explore · For US investors
A native Mac app — built for the platform, not ported to it — for measuring where you stand and where you're headed.
Securely link your brokerage to pull in holdings and balances automatically — a read-only connection that can never place trades or move money. This comes with ZBee Pro (coming soon); the free app explores realistic sample data.
Explore how much you could spend each year, with projections built from your real balances and clear, adjustable assumptions. Tax and Social Security modeling is US-specific.
Your holdings live in a private database on your own computer and are never sent to our servers — they're read directly between your Mac and your brokerage. Connection tokens stay in the macOS Keychain.
ZBee never places trades or moves money. It only reads, so you can measure your situation with confidence.
There are plenty of retirement calculators. ZBee answers one question — how much can I safely spend? — and answers it from your real money, with real rigor you can check: every method is laid out in the methodology.
Most tools make you type in a balance and a guess at your mix. ZBee connects to your brokerages, sorts every holding into the right tax treatment, and prices it live — so the answer reflects what you actually own, not a rounded estimate.
Simple calculators assume the same return every year, which quietly overstates what's safe. ZBee replays thousands of market histories — including bad runs early in retirement — and reports the spend that holds up at the confidence level you choose.
Federal brackets, capital gains, the taxation of Social Security, state tax, required minimum distributions, withdrawal order, and Medicare IRMAA surcharges — modeled year by year. Your tax bill is an output of the plan, not a number you guess.
It models survivorship — the single-filer brackets and lost Social Security benefit that make a surviving spouse's years the tightest — and turns longevity into a planning horizon you can reason about, instead of a number you pull from the air.
Cloud planners custody your linked financial data on their servers. ZBee doesn't: connecting your accounts uses a thin broker that only authorizes the link, so your holdings and balances flow directly between your Mac and your brokerage's data provider — never through us. Connection tokens stay in the macOS Keychain, and it's read-only, so it never trades or moves money.
ZBee isn't trying to be your budget, your net-worth tracker, and your advisor. It does one thing — measure the most you can sustainably spend in retirement — and does it carefully. A native Mac app, free to explore, that does one thing well.
Because this software touches your money, and starting with one platform done well beats spreading thin across several. Building for Apple silicon first means ZBee can use the Mac's own security — the Secure Enclave and the macOS Keychain — instead of rolling its own and asking you to trust it. We don't custody your financial data: your holdings never leave your Mac for our servers, and connecting your accounts only authorizes a read-only link — nothing for us to breach.
Other platforms may follow as ZBee grows. Whatever comes next will be built for its platform — properly native, not a lowest-common-denominator port.
Most money apps custody your financial data on their servers. ZBee doesn't: your accounts, balances, and plans are stored only on your device, and the app talks to third parties only when you ask it to. Read the Privacy Policy for the details.
Free to explore on sample data — no account needed. Connecting your own accounts comes with an annual Pro subscription (coming soon). Built for Apple silicon Macs.
Free to explore · Annual Pro subscription · macOS on Apple Silicon · Built for US taxpayers
ZBee