Cash sitting in checking or a low-interest savings account earns almost nothing. See the gap in a year — and how much is actually safe to move.
The 4% target is an assumption, not a quote — high-yield savings rates move with the market, so change it to whatever you can actually get. This is an estimate; your real result depends on your balances and rates.
The same balance, earning the target rate instead of today's, compounded once a year. This is the extra money you'd have — the cost of leaving it where it is.
Not every dollar in checking should chase a rate — you need cash on hand for this month's spending, plus a buffer for the unexpected. Keep that liquid, move the rest. Here's how the app reasons about it.
That safe-to-move amount, at your target rate, earns about $140 a year — without touching the cash you need on hand. If your balance is already at or below what you keep liquid, there's nothing to move, and that's the right answer too.
Most checking accounts pay next to nothing — often around 0.01% a year. Many traditional savings accounts are barely better. Banks can offer those rates because the money is convenient and most people never move it. Meanwhile, high-yield savings accounts and money-market accounts have paid several percent, because they compete for deposits. The difference between what your cash earns now and what it could earn is the rate gap, and on a few thousand dollars it adds up to real money every year you leave it unaddressed.
Here's the simple version. If you hold $10,000 at 0.01%, you earn about a dollar a year. The same $10,000 at 4% earns roughly $400. Nothing about your life changed — same money, same access — but one version quietly hands you a few hundred dollars and the other doesn't. Over several years, with compounding, the gap widens further. That's the number this calculator puts in front of you.
The catch is that not all of a checking balance should move. You need enough on hand to cover the month's bills and spending, and a buffer on top for the things you can't predict — a car repair, a medical bill, an income gap. A common starting point is one month of spending plus a cushion you're comfortable with. Whatever is left above that line is the part that's genuinely idle, and that's the part worth moving to a higher rate. Moving money you'll need next week isn't optimizing; it's setting up an overdraft.
Treat every figure here as an estimate. Rates change constantly, so the target rate is an assumption you control — set it to what you can actually get, not a headline. The safe-to-move figure depends entirely on your own spending and how large a buffer helps you sleep at night. The point isn't a precise forecast; it's to show whether the gap is big enough to bother with. For most people carrying idle cash, it is — and the fix is a one-time transfer, not a lifestyle change.
It depends on your balance and rate. Enter both above and the calculator shows the yearly gap between what you earn now and what you'd earn at a higher rate. For many people holding a few thousand dollars in idle cash, it's a few hundred dollars a year.
A savings account that pays a rate closer to market rates than a typical checking or legacy savings account. They're widely available, keep your money accessible, and are the usual home for cash you don't need day to day. This page doesn't recommend any specific bank or product.
It's an assumption, not a promise. High-yield rates move with the broader market and have sat in that range at times, but they change. Set the target rate to whatever you can actually get today.
Enough to cover the month's spending plus a buffer for the unexpected. The calculator's safe-to-move section lets you enter both, then shows what's left over to move without touching the cash you need on hand. If you're sizing that cushion, the emergency fund calculator goes deeper.
Moving money you genuinely don't need in the short term is low-risk — you're changing where cash sits, not investing it. The risk is moving too much and coming up short before payday, which is exactly what the buffer is there to prevent. This is an estimate and educational, not financial advice.
This is one account. Connect yours and Thryvest finds idle cash automatically across every account — then shows the exact move, in real dollars.
Create your account →Read-only via Plaid · it never moves your money.