Weekly Savings Needed Calculator

How it works

A weekly plan solves the same problem as a monthly one, in amounts that match how people are paid. The calculator grows the money you have already saved, then solves for the weekly deposit that covers the rest. Deposits land at the end of each week and interest compounds weekly, so the formula reads like this:

• W — the weekly deposit you are solving for
• G — your goal
• P — what you have already saved
• i — weekly interest rate (annual rate ÷ 52)
• n — number of weeks

With the defaults above, your $5,000 grows to about $6,106 on its own over five years at 4%. That growth leaves roughly $18,894 for your deposits to cover. The weekly deposit that closes the gap is about $65.67, or close to $285 a month.

That 4% stands for the annual percentage yield (APY) a bank quotes on a savings account. The formula divides that yield by 52 to get the weekly rate. Banks reprice the APY as macroeconomics shifts, so use the rate your account pays today, not the one you saw last year.

✓ Every result is checked against independent reference math. See how we test the calculators →

How to use this calculator

1. Enter your goal amount, the total you need in the account.
2. Add what you have already saved, so the calculator only solves for the gap.
3. Set the deadline, either a number of weeks or the date you need the money.
4. Type in the APY your savings account actually pays, not a hoped-for return.
5. Read the weekly deposit, then check the monthly equivalent shown beside it.

A worked example: $25,000 in five years

Say you want $25,000 for a down payment in five years and already have $5,000 set aside, earning 4% along the way. At that pace you would need to put away $65.67 a week, about $285 a month, to hit the goal by July 2031.

Your $5,000 head start grows while 260 weekly deposits add up to $17,074. Interest earned adds another $2,897, leaving a balance of $24,972 by July 2031, within a few dollars of the goal.

Where you keep the money matters. Leave it in cash at 0% and you would need $76.92 a week. Move it to index funds at 7% and the same goal takes just $57.57 a week, a $19 gap every week.

Swap in your own goal and timeline to see your number.

How do you keep the weekly transfer going?

The weekly figure only helps if the transfer actually happens. Automation is the personal finance habit that does that work for you.

• Automate it on payday: a standing transfer out of your checking account moves the money before you notice it.
• Round the number up: the next round figure costs little and covers a week you miss.
• Keep the goal separate: its own high-yield account, or a money market account, keeps that cash out of everyday spending.
• Raise it with your income: a dollar or two more a week after a raise pulls the finish date forward.
• Check the interest rate twice a year: if that account now pays less, run the goal again so the date still holds.

Weekly, biweekly, or monthly: does the cadence matter?

Splitting a goal into weekly amounts rather than monthly ones barely changes what you put in. Money deposited sooner earns only a few days of extra interest.

Economically the two are the same, so the choice comes down to how you are paid. If your pay lands every Friday, saving every Friday moves the money before you can spend it. That $65.67 a week also reads as easier than nearly $285 a month.

Run the same target through the monthly deposit calculator and the totals hardly move.

When is a weekly savings plan the wrong tool?

Saving on a schedule assumes you have no credit card debt. Money sitting in a savings account at 4% while a credit card charges 20% costs you every week, so clear that balance first.

Timing is the other limit. You cannot wait 30 weeks for a boiler that fails in January. That deadline is why some homeowners open a home equity line of credit (HELOC) or take a fixed-rate home equity loan.

Both cost less than a credit card, but a HELOC carries a variable rate. Either loan also puts your house at risk behind your mortgage, so you either save up or finance the purchase.

Every week of deposits into a home repair fund is money you never pay interest on. A bigger down payment works the same way later, shrinking the mortgage you sign.

A worked example: a nearer goal

Change the goal and the weekly number moves with it. Say you want $6,000 for a vacation in two years, starting from nothing, with the cash in a high-yield account at 4%. The weekly amount comes to about $55, or roughly $240 a month, and interest adds a little over $230.

• Add a head start: begin with $1,000 already saved and the weekly figure drops to about $45.
• Shorten the deadline: the same $6,000 in one year roughly doubles the weekly amount, to around $113.
• Save on payday instead: about $240 a month, or $120 a fortnight, lands in the same place as $55 a week.

Put your own numbers into the calculator, with the date you need the vacation money ready.