Income tax calculator — old vs new regime
See which regime actually costs you less, before you commit to one.
Deductions (used by the old regime only)
New regime
Old regime
FY 2025-26 slabs, resident individual below 60. Rebate u/s 87A applied (marginal relief and surcharge above ₹50L not modelled).
Figures are indicative. Thresholds, surcharge and current-year notifications are not fully modelled — confirm edge cases with your CA.
What this calculates
Since the new regime became the default, the choice is no longer academic — it is a calculation that has to be run for each person, each year. The new regime has wider slabs and lower rates but strips out most deductions; the old regime keeps the deductions and charges more on the same income. Which wins depends entirely on how much a person actually claims, which is why a rule of thumb does not survive contact with a real salary structure.
How it is worked out
- 1Both regimes start from gross total income for the year.
- 2The old regime subtracts the deductions you claim — chapter VI-A investments, house-property interest, and the rest — before applying its slab rates.
- 3The new regime applies its own wider slabs to income with most of those deductions disallowed, and offers a standard deduction against salary.
- 4Each result then takes the applicable rebate, surcharge where income is high enough, and health and education cess.
- 5The lower of the two totals is the regime worth choosing for that year.
Worked example
The comparison the calculator runs: the same gross income, once through each set of slabs.
- Gross income
- the same in both
- Old regime
- less deductions, then old slabs
- New regime
- few deductions, then new slabs
- Choose
- whichever total is lower
Common questions
Which is better, the old or the new tax regime?
It depends on how much you deduct. The new regime usually wins for someone with few deductions, because its rates are lower. The old regime wins once deductions are large enough — a full 80C, health insurance, and home-loan interest together often tip it. There is no threshold that holds for everyone, which is why it is worth calculating both.
Can I switch between the old and new regime?
A salaried taxpayer without business income can choose afresh each year when filing. A taxpayer with business income has far less flexibility — the option to switch back is restricted and, once exercised, generally cannot be repeated.
Which deductions are not available under the new regime?
Most chapter VI-A deductions, including 80C investments, are not available, nor is HRA exemption or the deduction for interest on a self-occupied house property. A standard deduction against salary income does apply. The employer's contribution to the pension scheme remains deductible.
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