Free Calculator
Capital Gains Tax Calculator
Estimate the capital gains tax on a share sale: your gain, the 50% CGT discount if you held the parcel more than 12 months, and the tax at your marginal rate.
How this is calculated ▸
- Capital gain — sale proceeds minus the adjusted cost base, including the purchase price, buy brokerage, sale costs and any cost-base adjustment you enter.
- Losses before discount — capital losses you enter reduce the gain before the 50% discount is applied.
- 50% discount — applied to the remaining gain on assets held more than 12 months, for individuals and trusts. SMSFs get 33⅓%; companies get none.
- Estimated tax — the taxable (discounted) gain at the marginal rate you enter.
- What's not modelled — the Medicare levy, SMSF/company rates, wash-sale issues, all CGT events, or whether a carried-forward loss is valid. Verify with a registered tax agent.
Adjusted cost base
$10,040
Capital gain
$4,960
Taxable gain
$2,480
After 50% discount
Estimated tax
$794
After-tax gain: $4,166
How your capital gain is taxed
This is an estimate for one parcel. Metrifly calculates CGT across every parcel automatically — with the discount, entity rules and cost-base adjustments applied.
From one sale to a full CGT report
A single share sale looks simple: sale proceeds minus cost base. In a real portfolio, the hard part is collecting every parcel, brokerage cost, AMIT adjustment, DRP parcel and capital loss in the right order. Use the calculator above to estimate one disposal, then use a portfolio-level CGT report for shares when you need the figures you will actually reconcile for myTax or your accountant.
Cost base
Include the quiet adjustments
Brokerage, sale costs and AMIT cost-base increases or decreases can change the gain even when the headline buy and sell prices look obvious.
Losses
Apply losses before discounts
Capital losses reduce capital gains first. Only then do eligible individuals and trusts apply the 50% discount to the remaining gain.
Lots
The parcel you sell matters
FIFO, LIFO or minimise-CGT allocation can produce different outcomes when you bought the same holding in several parcels.
What to reconcile before lodging
Check the acquisition date, disposal date, proceeds, brokerage, sale costs, capital losses and any managed-fund AMIT adjustments against your contract notes and annual tax statements. This calculator is general information and uses the individual/trust 50% discount assumption; SMSFs, companies and unusual events can differ. Verify the result with a registered tax agent before lodging.
FAQ
Questions about capital gains tax
How is capital gains tax calculated on shares in Australia?
Your capital gain is the sale price minus the adjusted cost base, including brokerage, disposal costs and cost-base adjustments such as AMIT. Capital losses are applied before the discount. If you held the shares more than 12 months, individuals and trusts generally get a 50% CGT discount on the remaining gain.
What is the 50% CGT discount?
Individuals and trusts that hold an asset more than 12 months are taxed on only half the capital gain. SMSFs get a 33⅓% discount; companies get none. This calculator uses the 50% individual/trust rate.
What happens if I make a capital loss?
A capital loss isn't taxed. You can use it to offset capital gains in the same year and carry any unused loss forward to future years. Losses don't receive the CGT discount.
Is this calculator accurate for my situation?
It's an estimate for one disposal using the individual/trust 50% discount and the marginal rate you enter. It doesn't model SMSF or company rates, the Medicare levy, all CGT events, wash-sale issues, or your full tax return. Verify with a registered tax agent before lodging.
Want CGT calculated automatically across every parcel, with the discount and entity rules applied? See Metrifly Tax Reporting →