Savings Calculator

How this result is built

Grow a savings balance with monthly deposits and a compound annual rate.

Savings math is investment math with a calmer rate. The useful split is the same: money you deposited, and yield the balance earned. On a short horizon the deposits dominate. On a long one, the yield starts to show.

What the opening example is for

Enter the yield you actually receive after the account’s compounding, or the stated rate if you know it compounds monthly. A promotional rate that expires should not be typed in as if it lasts the full term.

The walkthrough below uses the numbers already sitting in Savings Calculator. Press Calculate and the headline should match this page. Then put your own figures in. The math does not run until you press the button, and Clear hides the result.

What each field is doing

The “Current savings” line on Savings Calculator starts at $2,500.00. Leave that figure only when it matches the statement, the quote, or the plan you are testing. Press Calculate after the edit so the chart and the schedule move with it.

Savings Calculator treats “Monthly deposit” as its own entry, and the form opens with $300.00. A round example is useful for learning the page. It is a poor substitute for the number on your own paperwork, so replace it and run the form again.

The remaining fields

Before you replace it, “Annual yield” reads 4% on Savings Calculator. The other fields stay put while you change this one. That is the clean way to see what this line is doing inside the result.

Look at “Years” first if you are checking Savings Calculator: the filled value is 5. If the label is a rate, type the annual figure the contract uses. If it is money, type the amount that will actually move, not a rounded hope.

The opening result, line by line

Press Calculate on the opening form and Future value is $22,942.18. That is the number the rest of this section is talking about.

Contributed is $20,500.00 when you run the opening figures on Savings Calculator. That line is part of the same calculation as the headline. It is not a second balance you can spend on top of the result. Change one input and press Calculate if you want to see whether this line moves.

On this opening pass, growth is $2,442.18. That line is part of the same calculation as the headline. It is not a second balance you can spend on top of the result. Change one input and press Calculate if you want to see whether this line moves.

How those lines were produced

Contributions are added at the end of each compounding period.

The formula line on the page is A = P(1 + r/n)^(nt) + contribution growth. It is there so you can see the relationship the buttons are using. A schedule, when the page draws one, is that same series written row by row.

A second pass changes only “Current savings”, from $2,500.00 to $2,750.00. Future value moves from $22,942.18 to $23,247.43. Nothing else on the form was edited, so the gap between those two results is the effect of that one field on Savings Calculator. If the gap is tiny, this page is not very sensitive to that entry. If the gap is large, get that entry from a document before you plan around the result.

What this page will not claim

Savings Calculator compounds the rate you type. Markets do not pay a flat rate, and a fund fee comes out of the return before you should type it. The page is the equation, not a forecast and not a recommendation to buy or sell.

Savings Calculator stops at its own formula. When the next question is different, open Savings Goal Calculator (The deposit that hits a dated goal.); Compound Interest Calculator (Interest that starts earning interest of its own.); Emergency Fund Calculator (Months of essential costs, and the gap left.). Do not add those results to this one as if they were the same kind of dollar.

Check the result before you use it

Start on Savings Calculator by reading the labels, not the headline. The opening labels are Current savings ($2,500.00), Monthly deposit ($300.00), Annual yield (4%), Years (5). If a label is not the fact you have, the result cannot turn into that fact later. The illustration on the form lands on $22,942.18. When you press Calculate and see that same figure, the button and this explanation are using one formula.

Change one field at a time. Write down the headline, edit a single line, and press Calculate again. A large jump means that line carries the result. A line that does not move is a line the formula ignores, which is a reason to confirm you opened the right page. Savings Calculator is built for one job: What a monthly deposit becomes. The description on the page says the same thing in a sentence: Grow a savings balance with monthly deposits and a compound annual rate.

When the paperwork disagrees

Then hold the headline next to a source outside the site. That source might be a loan estimate, an account statement, a pay stub, or the public limit named in the methodology. A few cents of difference on a long schedule is ordinary rounding. A different rate, a fee you never typed, or a tax the form does not ask for is not rounding. Correct the input. Do not average the page with the paperwork.

When the outside source still disagrees, Savings Calculator has reached the edge of what it will claim. It will not phone a lender, pull a county record, or apply a credit you left blank. Send the calculator name, every input, and the result you expected through the contact page if you think the formula itself is wrong. Until that is settled, read $22,942.18 as the output of the fields above and nothing else.

FAQs