🔢 方案对比

📐 计算公式与说明

等额本息月供 月供 = [本金 × 月利率 × (1+月利率)期数] ÷ [(1+月利率)期数 − 1]
等额本金月供 每月本金 = 总本金 ÷ 期数
当月利息 = 剩余本金 × 月利率
月供 = 每月本金 + 当月利息(逐月递减)
演算示例(方案A:等额本息 vs 方案B:等额本金,均100万/30年/3.5%) 方案A(等额本息):月供=4,490元,总利息≈616,560元
方案B(等额本金):首月月供=5,694元,末月月供≈2,786元,总利息≈526,458元
方案B节省利息≈90,102元,但前期月供高约1,204元

📌 等额本息和等额本金有什么区别?

等额本息每月还款额固定,适合收入稳定者;等额本金前期还款高、后期低,总利息更少。中国房贷多采用等额本息,美国房贷以等额本息(30yr fixed)为主。

📌 什么是APR?和中国"年化利率"一样吗?

APR(年百分率)是美国贷款常用的年化利率指标,已包含某些费用。中国"年化利率"通常指合同利率,二者计算方法略有差异,但本计算器使用通用的名义年利率进行月供推算,适用于两国场景对比。

🔢 Compare Schemes

📐 Formulas & Notes

Equal Installment (Amortized) Monthly Payment Payment = [Principal × r × (1+r)n] ÷ [(1+r)n − 1]
Equal Principal Payment Principal per month = Total Principal ÷ n
Interest = Remaining Principal × r
Payment decreases each month
Example (Option A: amortized vs Option B: equal principal, both $100k/30yr/3.5%) Option A (amortized): monthly=$449, total interest≈$61,656
Option B (equal principal): first month=$569, last month≈$279, total interest≈$52,646
Option B saves ~$9,010 in interest but starts $120 higher per month

📌 Amortized vs Equal Principal?

Amortized loans have equal payments; equal principal loans pay down principal faster, saving total interest but with higher initial payments. U.S. mortgages are typically amortized over 30 years.

📌 What is APR?

APR (Annual Percentage Rate) reflects the true annual cost including some fees. In China, the "annualized rate" often refers to the contractual rate. This calculator accepts the nominal annual rate for comparison.