What is Income Tax Calculator?
Calculate income tax under old and new tax regime for FY 2024-25 and find which saves you more tax Simply enter your values, and the calculator instantly computes accurate results using standard financial formulas. All calculations are performed entirely in your browser — nothing is stored or transmitted.
Reviewed and last updated on 1 August 2026 by the FinCalc Pro Editorial Team.
How the Calculator Computes Tax in Both Regimes
The Income Tax Calculator mirrors the ITR computation exactly. It starts with your gross salary, subtracts the standard deduction (₹75,000 in the new regime, and the same in the old regime since FY 2023-24), then applies the deductions you enter — Section 80C investments, 80D health premiums, HRA exemption, and home loan interest under Section 24(b) for the old regime. The resulting taxable income is pushed through the slab rates for each regime separately.
A common source of confusion is that the two regimes are not just "different rates" — they have different slab structures entirely. The new regime compresses the slabs with a broader 5% band and a higher rebate, while the old regime taxes lower slabs more gently but expects you to fund your own deductions. The calculator runs both tracks and shows which leaves you with more take-home pay.
The Rebate Trap and the Marginal Tax Jump
Section 87A provides a full rebate for incomes up to ₹7 lakh in the new regime (₹5 lakh in the old regime). The consequence is a steep cliff: at ₹7,00,001 of taxable income, the rebate disappears and the tax jumps from zero to roughly ₹22,500 (plus cess). If your taxable income lands just above ₹7 lakh, planning even ₹1–2,000 of additional deductions or NPS contributions can be disproportionately valuable.
The calculator exposes this cliff clearly if you move the income input past the threshold. It is exactly the kind of "income almost crosses a line" situation where running the numbers instead of guessing saves the most money.
What the Old vs New Decision Really Depends On
Your total deductions are the deciding factor. If you claim ₹1.5 lakh under 80C, ₹25,000 in 80D, and ₹2 lakh in home loan interest, the old regime almost always wins. If you claim very little — no 80C, no HRA, no home loan — the new regime's lower slabs and higher rebate win. The crossover typically sits around ₹3.5–4 lakh of combined deductions for a ₹10–15 lakh salary.
Note that the new regime still allows the standard deduction and the employer NPS contribution under 80CCD(2), so "no deductions at all" is not strictly true. Enter everything honestly in both columns, and let the calculator do the comparison — the answer is rarely the same for two people with identical salaries but different deduction habits.
Formula Used
New regime slabs: 0% (0-3L) | 5% (3-7L) | 10% (7-10L) | 15% (10-12L) | 20% (12-15L) | 30% (above 15L) | Standard deduction: ₹75,000
How to Use This Calculator
- Enter your gross annual salary or income
- Enter applicable deductions (80C, HRA, NPS, etc.) for old regime
- Enter your employer NPS contribution if applicable
- Click Calculate to see tax under both regimes
- The calculator shows which regime saves you more tax
Worked Example
Salary: ₹12,00,000 | 80C: ₹1,50,000 | HRA: ₹1,20,000 → Old Regime Tax: ₹93,600 | New Regime Tax: ₹83,200 → New regime saves ₹10,400
Why Use This Tool?
- Compare old vs new tax regime instantly
- Find which regime gives maximum tax savings
- Includes standard deduction and all major deductions
- Updated for FY 2024-25 tax slabs
Frequently Asked Questions
What are the new tax regime slabs for 2024-25?
New regime: 0% up to ₹3L, 5% for ₹3-7L, 10% for ₹7-10L, 15% for ₹10-12L, 20% for ₹12-15L, 30% above ₹15L. Standard deduction of ₹75,000 is available.
Which tax regime is better — old or new?
New regime is better if your total deductions (80C + HRA + others) are less than ₹3.75 lakhs. Old regime is better if you have higher deductions like large HRA, home loan interest, or 80C investments.
Is 80C deduction available in the new tax regime?
No. Section 80C, HRA, 80D, LTA and most deductions are not available in the new tax regime. Only the standard deduction of ₹75,000 is available.
What is the tax rebate under Section 87A?
Under new regime, tax rebate up to ₹25,000 is available if total income does not exceed ₹7 lakhs. Under old regime, rebate up to ₹12,500 for income up to ₹5 lakhs.
Explore more tax (india) calculators or try our other free financial tools.