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Savings & Investment Calculators

Project how your savings grow with compound interest and regular contributions. Calculate future balances, set realistic savings goals, and build a monthly budget — free calculators using real financial math.

Savings & Investment Calculators

Project your financial future with accurate compound interest math.

Savings Calculator

Project your savings growth with regular contributions and compound interest.

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Compound Interest Calculator

See how compound interest multiplies your money over time.

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Budget Calculator

Create a monthly budget plan based on the 50/30/20 rule.

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The Power of Compound Interest

Compound interest is the mechanism that turns consistent saving into wealth over time. Unlike simple interest (which only earns returns on the original principal), compound interest earns returns on both the principal and all previously earned interest. The result is exponential growth that becomes increasingly powerful over longer time horizons.

The key variables in any savings calculation are: initial deposit, regular contributions, annual interest rate, compounding frequency, and time. Of these, time is often the most impactful. Starting 10 years earlier can result in twice the final balance, even with identical contributions, because early dollars have more years to compound.

A common benchmark: the "Rule of 72" estimates how long it takes money to double at a given rate. Divide 72 by the annual rate. At 6%, money doubles in 12 years. At 8%, in 9 years. At 10%, in 7.2 years. This simple mental model illustrates why rate of return and time horizon are so powerful — and why starting early matters so much.

Common Savings Goals & Benchmarks

Emergency Fund

3–6 months of living expenses in a high-yield savings account or money market fund. This is the foundation of any financial plan — it prevents unexpected expenses from derailing long-term goals. At current HYSA rates of 4–5%, your emergency fund earns meaningful interest while remaining accessible.

Retirement Savings

Fidelity's benchmark: have 1× your salary saved by age 30, 3× by 40, 6× by 50, 8× by 60, and 10× by 67. Contributing at least enough to capture your employer's 401(k) match is the absolute minimum — it's an immediate 50–100% return on invested dollars. Beyond the match, maximize tax-advantaged accounts (401k, IRA, HSA) before taxable investing.

Home Down Payment

Saving 20% down eliminates PMI and significantly reduces your monthly payment. With median US home prices around $420,000 in 2026, that's $80,000. At $1,000/month in a 5% APY account, you can accumulate $80,000 in about 6.3 years. Use our Savings Calculator to model any specific scenario with your target amount and timeline.

How Rate of Return Affects $500/Month Over 20 Years

Annual RateWhere You Find ItFinal BalanceInterest Earned
2%Regular savings account$147,596$27,596
4%High-yield savings / CD$183,237$63,237
6%Conservative portfolio$232,175$112,175
8%Balanced portfolio$298,072$178,072
10%Stock-heavy portfolio$386,996$266,996

$500/month contributions starting from $0, compounded monthly for 20 years. Total contributions = $120,000.

Frequently Asked Questions

High-yield savings accounts (HYSA) offered by online banks are the best combination of safety, liquidity, and return. In 2026, top HYSAs are paying 4–5% APY — significantly above the national average savings rate of under 0.5%. The money is FDIC insured up to $250,000, accessible within 1–3 business days, and earns meaningful interest while you wait.
More frequent compounding means slightly more interest earned. Daily compounding earns slightly more than monthly, which earns more than quarterly, which earns more than annual. In practice, the difference between daily and monthly compounding at typical savings rates (4–7%) is small — less than 0.5% difference in final balance over 10 years. The interest rate and time horizon matter far more than compounding frequency.
Most financial planners recommend saving 15% of gross income for retirement (including any employer match). At a minimum, contribute enough to get your full employer 401(k) match — it's an immediate 50–100% return on investment. The earlier you start, the lower your required savings rate. Someone starting at 25 can likely retire comfortably saving 10–12%; someone starting at 40 may need 20–25%.
Both serve different purposes. Savings (HYSA, CDs, money market funds) are for money you need within 1–5 years — emergency fund, home down payment, near-term goals. Investing (stocks, bonds, index funds) is for money you won't need for 5+ years, where you can tolerate short-term volatility in exchange for higher long-term returns. The general order: build emergency fund first, then capture employer 401k match, then max tax-advantaged accounts, then invest in taxable accounts.