Savings Calculator
Project growth, or work backward from a goal. High-yield savings accounts pay 4–5% these days; CDs and treasuries pay similar.
Results
Final balance
$0
Total contributed
$0
Interest earned
$0
APY vs APR
Bank-savings rates are usually quoted as APY (annual percentage yield) — what you actually earn over a year including compounding. Loan rates are usually APR (annual percentage rate) — the nominal rate before compounding. For a savings calculator, APY is the right input.
The formula
- A = final balance
- P = starting balance
- r = annual rate (APY, as a decimal — 4.5% is 0.045)
- t = years
- C = monthly contribution
"Reach a goal" mode runs the same formula backward — it solves for the monthly contribution C that grows P to a target balance A over t years, instead of solving for A directly.
Worked example
Project balance: $5,000 starting balance, $300/month, 4.5% APY, 5 years → final balance $26,402.64 ($18,000 contributed, $3,402.64 earned in interest).
Reach a goal: same $5,000 starting balance and 4.5% APY, but aiming for a $50,000 goal in 5 years instead of projecting forward — the required monthly contribution comes out to $651.44. Feed that number back into the project-balance formula and it lands on exactly $50,000, which is what "Reach a goal" mode is solving underneath.
Frequently asked questions
What's a realistic APY to use?
High-yield online savings accounts have paid roughly 4–5% in recent years. CDs and short-term treasuries land in a similar range depending on the term. A checking account or a savings account at a large traditional bank often pays close to 0% — worth checking before you assume 4–5%.
Does compounding frequency matter much for a savings account?
Not really at typical bank rates. Monthly compounding (what this calculator uses, matching how most banks actually credit interest) gets you within pennies of daily compounding over a multi-year horizon. It matters far more for loans, where the stated rate is APR rather than APY.
How is "Reach a goal" mode different from just guessing a contribution?
It solves the compound-interest formula algebraically for the contribution instead of making you try numbers until the projected balance happens to land near your goal. Same math, just run in reverse.
Is my money FDIC-insured in a high-yield savings account?
If it's a deposit account at an FDIC member bank, yes — up to $250,000 per depositor, per bank, per ownership category. Some "high-yield savings" products offered by fintech apps route your money to a partner bank for that coverage; a money-market fund (as opposed to a money-market deposit account) is not FDIC-insured at all. Check the fine print before assuming.