Basic Tax Calculation (IN)

calculate_tax.py

#!/usr/bin/python3

def cal_taxable_income(income, deductions, regime):
    taxable_income = income
    if regime == 'old':
      taxable_income -= deductions
    return taxable_income

def income_tax_calculator(income, deductions, rules, regime):
    taxable_income = cal_taxable_income(income, deductions, regime)
    print(f'{"*" * 5}\tIncome\t\t: {income}\t{"*" * 5}')
    print(f'{"*" * 5}\tDeductions\t: {deductions}\t{"*" * 5}')
    print(f'{"*" * 5}\tTaxable\t\t: {taxable_income}\t{"*" * 5}')

    _tax = 0
    for _key, rule in rules.items():
        if taxable_income <= rule["start"]: break
        if taxable_income <= rule["end"]:
            rule["end"] = taxable_income

        print(f'\n{"*" * 5} Rule {_key + 1} : Start = {rule["start"]} | End = {rule["end"]} | Tax = {rule["tax"] * 100}% {"*" * 5}')
        _tax += ((rule["end"] - rule["start"]) * rule["tax"])
        print(f'{"*" * 5}\tTax : {_tax}')
    
    net_income = taxable_income - _tax
    if regime == 'old':
      net_income += deductions

    print(f'\n{"*" * 8}\tNet Income : {net_income}\t{"*" * 5}')
    print(f'{"*" * 8}\tTotal Tax : {_tax}\t{"*" * 5}')   

income = float(input('Enter total yearly income : '))
deductions = float(input('Enter total yearly deduction : '))

## Rules ##
slab_rules_19_20 = {
    0: {
        'start': 0,
        'end': 250000,
        'tax': 0
    },
    1: {
        'start': 250000,
        'end': 500000,
        'tax': 0.05
    },
    2: {
        'start': 500000,
        'end': 1000000,
        'tax': 0.20
    },
    3: {
        'start': 1000000,
        'end': cal_taxable_income(income, deductions, 'old'),
        'tax': 0.30
    }
}

## New Regime Rules ##
slab_rules_fy_20_21 = {
    0: {
        'start': 0,
        'end': 500000,
        'tax': 0
    },
    1: {
        'start': 500000,
        'end': 750000,
        'tax': 0.10
    },
    2: {
        'start': 750000,
        'end': 1000000,
        'tax': 0.15
    },
    3: {
        'start': 1000000,
        'end': 1250000,
        'tax': 0.20
    },
    4: {
        'start': 1250000,
        'end': 1500000,
        'tax': 0.25
    },
    5: {
        'start': 1500000,
        'end': cal_taxable_income(income, deductions, 'new'),
        'tax': 0.30
    }
}

slab_rules_fy_24_25 = {
    0: {
        'start': 0,
        'end': 300000,
        'tax': 0
    },
    1: {
        'start': 300000,
        'end': 600000,
        'tax': 0.05
    },
    2: {
        'start': 600000,
        'end': 900000,
        'tax': 0.10
    },
    3: {
        'start': 900000,
        'end': 1200000,
        'tax': 0.15
    },
    4: {
        'start': 1200000,
        'end': 1500000,
        'tax': 0.20
    },
    5: {
        'start': 1500000,
        'end': cal_taxable_income(income, deductions, 'new'),
        'tax': 0.30
    }
}

slab_rules_fy_25_26 = {
    0: {
        'start': 0,
        'end': 400000,
        'tax': 0
    },
    1: {
        'start': 400000,
        'end': 800000,
        'tax': 0.05
    },
    2: {
        'start': 800000,
        'end': 1200000,
        'tax': 0.10
    },
    3: {
        'start': 1200000,
        'end': 1600000,
        'tax': 0.15
    },
    4: {
        'start': 1600000,
        'end': 2000000,
        'tax': 0.20
    },
    5: {
        'start': 2000000,
        'end': 2400000,
        'tax': 0.25
    },
    6: {
        'start': 2400000,
        'end': cal_taxable_income(income, deductions, 'new'),
        'tax': 0.30
    }
}

print(f'\n{"*" * 10} Old Regime {"*" * 10}')
income_tax_calculator(income, deductions, slab_rules_19_20, 'old') # Old Regime

print(f'\n{"*" * 10} New Regime FY24-25 {"*" * 10}')
income_tax_calculator(income, deductions, slab_rules_fy_24_25, 'new') # No deduction available in New Regime

print(f'\n{"*" * 10} New Regime FY25-26 {"*" * 10}')
income_tax_calculator(income, deductions, slab_rules_fy_25_26, 'new') # No deduction available in New Regime