Finance & Investment · Returns
Post-tax Return Calculator
Turn a pre-tax return into your post-tax return for interest taxed every year (FDs, bonds), gains taxed once when you sell (mutual funds, shares) or tax-free income (PPF) — and compare all three for the same return to see the cost of paying tax every year.
Your inputs
Quick start — try a typical case
₹ 10 lakh
Your slab rate for interest; 12.5 % for long-term equity gains; 20 % for short-term equity.
Your result Live
Post-tax Return
5.16%
7.50% before tax · 31.20% tax every year
- ₹10,00,000 Grows To (after tax)
- ₹16,53,887
- Tax Paid
- ₹4,07,145
- Gain You Keep
- ₹6,53,887
- Same Return Taxed Only at Exit
- 5.63% — ₹76,103 more
- Invested · 49%₹10,00,000
- Gain kept · 32%₹6,53,887
- Tax · 20%₹4,07,145
The same 7.50% return, taxed three ways
3 rowsPaying tax every year shrinks the amount that compounds; tax paid once at the end lets the whole gain compound first (tax deferral).
Surcharge, the 87A rebate and indexation aren't modelled. Interest income is taxed on accrual even in a cumulative FD.
How this is calculated
Yearly tax: V = A(1 + r(1 − t))ⁿ · At exit: V = A(1 + r)ⁿ − t·max(0, gain − exemption) · Post-tax return = (V/A)^(1/n) − 1
- t
- Tax rate (with 4 % cess if selected: slab × 1.04)
- n
- Years invested
An FD at 7.5 % in the 30 % bracket really earns about 5.2 % after tax — and less than a fund that earns the same 7.5 % but is taxed only when you sell, because that tax is deferred while the full amount compounds. Use this to compare investments on what you actually keep.
Assumptions & sources
- Constant pre-tax return; tax on yearly interest paid from the investment each year.
- Capital-gains tax paid once at the end, on the gain above any exemption; no tax refund on losses.
- Indian rates for reference (checked 2026-10-10): long-term equity gains 12.5 % above ₹1,25,000, short-term 20 %; interest and debt-fund gains at your slab rate.
- 1Capital gains on listed equity shares and equity-oriented mutual funds — Income Tax Department
- 2Income-tax slabs and cess — Income Tax Department
- 3Investments (Bodie, Kane & Marcus), chapters on returns, compounding and the time value of money — McGraw-Hill
Calculator ID FIN-RET-POSTTAX-001 · version 1.0.0
Common questions
What is the post-tax return on an FD?
Rate × (1 − your tax rate with cess). A 7 % FD in the 30 % slab (31.2 % with cess) nets about 4.8 % a year.
Why does tax deferral matter?
Money you'd have paid in tax each year stays invested and compounds. Over long periods that adds up — see the comparison table.
Is the 4 % cess applied to capital gains too?
Yes. Health and education cess is 4 % of the tax, whatever the income type.