Work out the tax before you press sell — today’s rules and the proposed 2027 rules, side by side.
Pop in your buy and sell parcels and we’ll do the CGT maths the way the ATO does — 50% discount, losses, your marginal rate and the 2% Medicare levy, all in. Everything runs right here in your browser, so your numbers never leave your screen.
Selling shares, an ETF or some crypto and wondering what the tax bill looks like? This free CGT calculator works it out the same way the ATO does: gross gain per parcel, the 50% CGT discount for anything you’ve held longer than 12 months, any capital losses you’re carrying, then the net gain stacked on top of your income at the right financial-year bracket plus the 2% Medicare levy. You’ll see your tax payable, effective rate and exactly what lands in your pocket after the sale. And because the 50% discount is set to change, there’s a one-of-a-kind toggle that shows today’s rules next to the proposed post-1-July-2027 indexation rules — a side-by-side no other calculator gives you.
Fill in dates, price & quantity
Salary, business and other income for the financial year — the gain is added on top.
Realised capital losses from other sales this financial year.
Net capital losses from prior years you haven't used yet.
Add your first parcel — buy date, price, quantity and brokerage — and your CGT updates live as you type. Nothing is saved or sent anywhere.
Here’s the recipe, in plain English — every number traced back to the ATO rule it comes from, so you can check our working.
Work out the capital gain on each parcel
For every parcel we take your sale proceeds and subtract the cost base — what you paid for the shares plus buying and selling brokerage and other incidental costs. Proceeds minus cost base is your gross capital gain (or capital loss) on that parcel, exactly as the ATO defines it under the CGT cost-base rules.
Apply capital losses before any discount
Current-year capital losses are applied first, then losses carried forward from earlier years, and they come off your gains before the 50% discount. We offset them against your non-discountable gains first (the ATO lets you choose the order), because a dollar of loss wipes out a whole dollar of an undiscounted gain but only half a dollar once the discount applies — so you keep more of the discount.
Apply the 50% CGT discount to long-held parcels
Any parcel held for more than 12 months — counted exclusive of both the buy date and the sell date — gets the 50% CGT discount for individuals (33⅓% for complying super funds, nil for companies and most foreign residents since 8 May 2012). We check each parcel’s holding period and halve only the gains that qualify.
Stack the net gain on your income at the right FY rate
Your net capital gain isn’t taxed at a separate rate — it’s added on top of your taxable income for the financial year and taxed at the marginal brackets that apply, plus the 2% Medicare levy. We use the correct brackets for the FY you choose (including the legislated 16%→15%→14% cuts) and handle bracket crossings, so the gain is taxed at the rates it actually lifts you into.
Show the 2027 proposed rules side by side
Flip to the 2027 tab and we re-run the same disposal under the proposed regime: cost-base indexation by CPI plus a minimum 30% tax rate on the net gain, with gains apportioned across the 1 July 2027 line so pre-2027 growth keeps the 50% discount. This is the Treasury Laws Amendment (Tax Reform No. 1) Bill 2026 — proposed, not law — so treat it as a what-if.
Your capital gain is the sale proceeds minus your cost base (what you paid plus brokerage and other buying/selling costs). If you owned the shares for more than 12 months, individuals knock 50% off the gain via the CGT discount. You then subtract any capital losses, and the net gain is added on top of your taxable income — so it’s taxed at your marginal rate for that financial year, plus the 2% Medicare levy. There’s no separate “CGT rate”; the gain simply lifts your income for the year.
Individuals (and trusts) get a 50% discount on a capital gain when the asset has been held for more than 12 months, counted exclusive of both the buy date and the sell date — so a hair over a year, not exactly 365 days. Complying super funds get 33⅓% instead, and companies get nothing. Foreign and temporary residents have been excluded from the discount on gains accrued since 8 May 2012. Our calculator checks each parcel’s holding period for you and flags which ones earn the discount.
The Government has proposed replacing the flat 50% discount with cost-base indexation (uplifting your purchase cost by CPI) plus a minimum 30% tax rate on net capital gains, for assets sold from 1 July 2027. Gains that accrued before that date keep the 50% discount and are apportioned. Important: this is the Treasury Laws Amendment (Tax Reform No. 1) Bill 2026 — it’s before Parliament and is NOT law yet, so it may change or not pass. Our 2027 toggle is there so you can see the likely difference; treat it as a what-if, not a tax return.
Yes. Capital losses — from this year or carried forward from earlier years — are subtracted from your capital gains before the discount is applied, and it’s smart to use them against gains that don’t qualify for the discount first, because a discounted gain only needs half as much loss to wipe out. Losses can only reduce capital gains, never your salary or other ordinary income, and any leftover loss carries forward indefinitely until you have a gain to use it on. Just punch in your available losses and we’ll order them for you.
Completely private. Every calculation runs in your own browser — your purchase prices, income and parcels are never sent to a server, never stored, and never seen by us. There’s no login, no email, no broker connection. Close the tab and it’s gone. That’s the whole point: you get Sharesight-style maths without handing over your credentials or your privacy.
Yes — the CGT mechanics are the same for listed shares, ETFs and crypto: proceeds minus cost base, the 12-month discount test, loss offsets and your marginal rate. The main wrinkle is that ETFs sometimes have AMIT cost-base adjustments from their annual tax statements, and crypto disposals include crypto-to-crypto swaps. Enter each disposal as its own parcel and the calculator treats it correctly; for ETF cost-base tweaks, adjust the cost base you enter to match your AMMA statement.
