Finance tools
APY calculator
Free APY calculator, annual percentage yield calculator, and high-yield savings calculator for HYSA shopping. Enter APY %, initial deposit, and optional monthly contributions for live ending balance and interest earned — or use Rate to APY mode as an interest rate to APY calculator and Compare to pit two savings offers side by side. Growth chart, yearly breakdown, CSV/PDF export, no sign-up.
What is APY?
APY (annual percentage yield) is the effective yearly return on a deposit account after compounding is included. Banks and credit unions quote APY on high-yield savings accounts (HYSAs), money market accounts, and CDs so you can compare offers on equal footing — the “A” always means annual, even when interest is credited daily or monthly.
Unlike a simple interest rate, APY reflects how often interest is credited. A 5% nominal rate compounded monthly yields a slightly higher APY than 5% compounded once per year. Use this tool when you already have a quoted APY; use our compound interest calculator for nominal-rate retirement or goal planning.
Grow savings from quoted APY
Project ending balance with initial deposit, optional monthly contributions, and daily/monthly compounding.
Interest rate → APY converter
Enter a nominal annual rate and compounding frequency to see the true APY % (Omni benchmark: 5% monthly → 5.12%).
Compare two APY offers
Side-by-side chart and interest delta when choosing between HYSA providers.
CSV/PDF export
Download inputs and results for spreadsheets or sharing — no account required.
Related finance tools: compound interest calculator, inflation calculator, savings bond calculator (Series I inflation component), and CAGR calculator for investment annualized returns.
APY formula
The standard APY formula converts a nominal annual interest rate and compounding frequency into an effective yearly yield:
APY formula
APY = (1 + r ÷ n)n − 1Where r is the annual nominal rate (decimal) and n is compounding periods per year (12 = monthly, 365 = daily). Multiply by 100 for APY %.
To calculate APY step by step:
- Divide the annual rate by n to get the periodic rate.
- Add 1, raise to the power n, then subtract 1.
- Multiply by 100 for a percentage — or use Rate to APY mode above.
Worked example: 5% interest rate compounded monthly (n = 12) → 5.12% APY. Some bank pages show ~$1,051 on $1,000 by compounding a 5% nominal rate monthly; when the product quotes 5% APY directly, true one-year interest is about $50 ($1,050 balance).
APY vs interest rate vs APR
Interest rate is the stated annual rate before compounding frequency is applied. APY is the effective annual return after compounding — so APY is usually slightly higher when interest compounds more than once per year. APR (annual percentage rate) applies to borrowing (loans, credit cards) and may include fees; do not compare loan APR to savings APY.
Same nominal rate, different compounding (illustrative):
- 5% nominal, monthly → 5.12% APY
- 5% nominal, quarterly → 5.09% APY
- 5% nominal, annually → 5.00% APY
When shopping for savings, compare APY (not APR). For long-horizon investing with contributions, see our compound interest calculator.
High-yield savings (HYSA) calculator
A high-yield savings calculator projects how much a competitive HYSA earns versus a traditional savings account. Top online banks often quote 4–5% APY in 2026, while FDIC-insured traditional savings averages near 0.5% nationally — so the spread on a $10,000 balance can exceed $350 per year.
Use Grow savings mode with your quoted APY, set daily compounding (typical for HYSAs), and add monthly contributions if you automate transfers. Then use Compare to model switching from a lower APY to a higher one.
How much does X% APY earn?
Engine-locked examples (true APY semantics, daily compounding unless noted):
- 5% APY on $1,000 (1 year): about $50 interest → $1,050 balance
- 4% APY on $10,000 (daily, 1 year): about $400 interest → $10,400 balance
- 3.65% APY on $10,000 (daily, 1 year): about $365 interest → $10,365 balance
- 4% APY on $1,000 (daily, 1 year): about $40 interest → $1,040 balance
- 3.5% APY on $1,000 (daily, 1 year): about $35 interest → $1,035 balance
APY with monthly contributions
Many savers search for an APY calculator with monthly deposits. In Grow savings mode, add a monthly contribution alongside your starting balance — interest compounds on the growing balance each period. Example preset: $10,000 at 4% APY plus $200/month for 10 years (daily compounding) shows how automated saving accelerates total interest versus interest on the initial deposit alone.
Daily vs monthly compounding
Most competitive HYSAs compound daily and quote APY accordingly. More frequent compounding means interest earns interest sooner — the gap versus monthly crediting is usually small at typical savings rates but matters when comparing fine-print details. This calculator defaults to daily compounding in Grow mode; open the advanced panel to switch to monthly, quarterly, or annual crediting if your account terms differ.
How to compare savings accounts
Use Compare mode to pit two APY offers against each other with the same deposit and contribution schedule. A 0.5–1.0 percentage-point APY gap can mean hundreds of dollars over a decade on five-figure balances. Check minimum balances, withdrawal limits, and whether the rate is promotional before switching — this tool models math only, not account rules or taxes.
Savings APY vs CDs and credit cards
This tool is for deposit APY — savings and HYSA growth — not CD maturity schedules or credit-card interest. Related searches for “APY calculator CD” or “credit card APY” usually mean either a fixed-term CD (locked rate, early-withdrawal penalties) or APR on borrowed balances (what you pay, not what you earn).
If you need investment growth with a nominal rate and long horizons, use the compound interest calculator. For purchasing power after inflation, pair results with the inflation calculator.
Limitations
Results are illustrative. Institutions may use slightly different day-count or rounding rules. This tool does not model taxes on interest, CD penalties, tiered rates, promotional rate cliffs, or variable rate changes. Not financial, tax, or investment advice.
How to use this calculator
Choose a mode
Grow savings (APY projection), Rate to APY (convert a quoted nominal rate), or Compare (two APY scenarios).
Enter your numbers
Set initial deposit, optional monthly contribution, APY %, years, and compounding frequency.
Review chart and export
See ending balance, interest earned, yearly breakdown, and download CSV or PDF when needed.
More free tools
Discover more calculators for time tracking, payroll, and HR.
Frequently asked questions about this APY calculator
What is APY?
APY (annual percentage yield) is the effective yearly return on a deposit account after compounding. Banks quote it on savings and HYSA products so you can compare yields on equal footing.
How do you calculate APY?
APY = (1 + r ÷ n)n − 1, where r is the annual nominal rate and n is compounding periods per year. Use Rate to APY mode above, or Grow savings when you already have a quoted APY.
What is the difference between APY and interest rate?
The interest rate is the stated annual rate before compounding. APY includes compounding, so APY is usually slightly higher when interest is credited more than once per year. Compare savings products using APY.
What is the difference between APY and APR?
APY applies to money you earn on deposits. APR applies to money you borrow on loans or credit cards and may include fees. Do not compare loan APR to savings APY.
What is 5% APY on $1,000?
With a true 5% APY for one year, a $1,000 deposit earns about $50 in interest for an ending balance near $1,050. Some bank examples show ~$1,051 by compounding a 5% nominal rate monthly — that is rate-to-APY math, not a quoted 5% APY.
What is 4% APY on $10,000?
At 4% APY for one year with daily compounding, $10,000 earns about $400 in interest — roughly $10,400 total.
What is 3.65% APY on $10,000?
At 3.65% APY for one year (daily compounding), $10,000 earns about $365 in interest — roughly $10,365 total.
Is 3.5% APY good for a savings account?
In 2026, 3.5% APY is well above the national average for traditional savings (~0.5%) and solid for a HYSA, though top online banks may offer 4–5% APY when rates are elevated. Compare fees, minimums, and withdrawal rules — not just the headline rate.
How do I convert interest rate to APY?
Use Rate to APY mode: enter the nominal annual rate and compounding frequency. Example: 5% compounded monthly → 5.12% APY.
Is this APY calculator for CDs or credit cards?
Savings and HYSA deposits. CD calculators model fixed terms and penalties; credit-card searches usually mean APR on debt. This tool projects deposit growth and converts nominal rates to APY — not loan or card payoff math.