个税计算器

复制import sys

# 累计预扣法计算当月个税（2025 标准）
# 输入：累计收入、累计免税收入、累计专项扣除、累计专项附加扣除、累计已预缴税额
# 输出：当月应补（退）税额

def calc_monthly_tax(income_cum, free_cum, special_cum, extra_cum, paid_cum):
    # 基本减除费用：5000 元/月，假设已累计 6 个月
    months = 6
    deduction = 5000 * months
    taxable = income_cum - free_cum - deduction - special_cum - extra_cum
    if taxable <= 0:
        return 0 - paid_cum  # 无需缴税，退回已缴
    # 综合所得税率表（2025）
    brackets = [(36000, 0.03, 0), (144000, 0.10, 2520), (300000, 0.20, 16920),
                (420000, 0.25, 31920), (660000, 0.30, 52920), (960000, 0.35, 85920),
                (sys.maxsize, 0.45, 181920)]
    for limit, rate, quick in brackets:
        if taxable <= limit:
            tax = taxable * rate - quick
            break
    return tax - paid_cum

# 示例：前 6 个月累计收入 120000，社保 12000，专项附加 18000，已缴 1500
result = calc_monthly_tax(120000, 0, 12000, 18000, 1500)
print(f"当月应补（退）税额：{result:.2f} 元")

复制package main

import (
	"fmt"
)

// 综合所得年度汇算清缴计算（2025 标准）
// 全年应纳税所得额 = 全年收入 - 60000 - 专项扣除 - 专项附加扣除 - 其他扣除
func annualTax(income, special, extra float64) float64 {
	taxable := income - 60000 - special - extra
	if taxable <= 0 {
		return 0
	}
	// 超额累进税率表
	type bracket struct {
		limit float64
		rate  float64
		quick float64
	}
	brackets := []bracket{
		{36000, 0.03, 0},
		{144000, 0.10, 2520},
		{300000, 0.20, 16920},
		{420000, 0.25, 31920},
		{660000, 0.30, 52920},
		{960000, 0.35, 85920},
		{1e18, 0.45, 181920},
	}
	for _, b := range brackets {
		if taxable <= b.limit {
			return taxable*b.rate - b.quick
		}
	}
	return 0
}

func main() {
	// 示例：年收入 250000，社保 24000，专项附加 36000
	tax := annualTax(250000, 24000, 36000)
	fmt.Printf("全年应纳税额：%.2f 元\n", tax)
}

复制// 月度个税计算（累计预扣法）
// 输入：当月收入、累计已缴、专项扣除、专项附加扣除
function monthlyTax(income, paid, special, extra) {
  // 假设当前为第 6 个月
  const months = 6;
  const deduction = 5000 * months;
  const taxable = income - deduction - special - extra;
  if (taxable <= 0) return -paid;

  const brackets = [
    { limit: 36000, rate: 0.03, quick: 0 },
    { limit: 144000, rate: 0.10, quick: 2520 },
    { limit: 300000, rate: 0.20, quick: 16920 },
    { limit: 420000, rate: 0.25, quick: 31920 },
    { limit: 660000, rate: 0.30, quick: 52920 },
    { limit: 960000, rate: 0.35, quick: 85920 },
    { limit: Infinity, rate: 0.45, quick: 181920 }
  ];

  for (const b of brackets) {
    if (taxable <= b.limit) {
      return taxable * b.rate - b.quick - paid;
    }
  }
  return 0;
}

// 示例：累计收入 120000，已缴 1500，社保 12000，专项附加 18000
console.log(`当月应补税额：${monthlyTax(120000, 1500, 12000, 18000).toFixed(2)} 元`);