How does compound interest work?

Compound interest means you earn interest on both your original principal and on the interest already accumulated. For example, €1,000 at 5% annual compound interest grows to €1,276 after 5 years — compared to €1,250 with simple interest. The more frequently interest compounds, the faster your money grows.

What is the difference between compound and simple interest?

Simple interest is calculated only on the original principal: Interest = P × r × t. Compound interest is calculated on the principal plus all previously earned interest. Over long periods, the difference is dramatic — €10,000 at 6% simple interest for 30 years gives €28,000, while compound interest gives €57,435.

How often should interest compound for the best return?

The more frequently interest compounds, the higher the effective return. Daily compounding produces slightly more than monthly, which produces more than annual. The difference is small for modest rates — at 5%, daily compounding yields an effective annual rate of 5.127% versus 5.0% for annual compounding.

What is the Rule of 72?

The Rule of 72 is a quick estimate of how long it takes to double your money: divide 72 by the annual interest rate. At 6%, your money doubles in approximately 12 years (72 ÷ 6 = 12). At 9%, it doubles in 8 years. It works best for rates between 4% and 15%.

How does inflation affect compound interest returns?

Inflation erodes the real value of your returns. If your investment earns 6% but inflation is 2.5%, your real return is approximately 3.5%. Our compound interest calculator includes an inflation adjustment so you can see the true purchasing power of your future savings.

📈 复利计算器

了解您的储蓄或投资如何随复利的力量而增长。包括通胀调整和定期缴款建模。

初始投资(€)

月供款（€）

年利率（%）

时间段(年)

复利频率

通货膨胀率（%）— 可选

⚠️ 仅供参考。 投资回报不保证。资本面临风险。过往业绩不能预测未来回报。非财务建议。

理解复利

复利是对本金及前期累计利息一并计算的利息。据称阿尔伯特·爱因斯坦曾称其为"世界第八大奇迹"——数学也印证了这一点。

公式为：FV = P(1 + r/n)^(nt) + PMT × [((1 + r/n)^(nt) − 1) / (r/n)]，其中P = 本金，r = 年利率，n = 复利频率，t = 年数，PMT = 定期付款额。

每日 vs 每年复利

复利频率越高，资金增长越快。7%的年利率按日复利的实际年利率（EAR）为7.25%，而按年复利则恰好是7%。在€10,000的基础上，20年后这一差距会复利成数千欧元。

72法则

用72除以您的年利率，估算您的钱翻倍所需的年数。以7%的利率，您的投资大约每10.3年翻一倍。

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重要提示： 本工具仅提供估算，不能替代专业建议。这些计算器生成的信息可能不完整，未能涵盖所有个人情况。在根据计算结果采取行动之前，请务必咨询经认证的专业人士（如财务顾问、医疗服务提供者或持牌工程师）。

📈 复利计算器

理解复利

每日 vs 每年复利

72法则

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