How to use the capital gains tax calculator
- Choose your country. The calculator picks it from your location, but you can change it.
- Enter the sale price, the purchase price and the costs of buying and selling (fees, commissions, stamp duty, improvements).
- Say how long you owned it (US and Australia) and enter your other income for the year, which sets the rate.
- Under Losses, add capital losses from other sales and, in the US, your own deductions if you itemise.
The tax shown is the extra tax the gain adds to your year: tax on your income with the gain, minus tax without it.
US: 2026 long-term capital gains rates
| Filing status | 0% up to | 15% up to | 20% |
|---|---|---|---|
| Single | $49,450 | $545,500 | above |
| Married filing jointly | $98,900 | $613,700 | above |
| Married filing separately | $49,450 | $306,850 | above |
| Head of household | $66,200 | $579,600 | above |
Example: single, $60,000 of other income, a $20,000 gain on shares held over a year. Taxable income before the gain is $60,000 − $16,100 standard deduction = $43,900. The first $5,550 of the gain fills the 0% band up to $49,450; the other $14,450 is taxed at 15%, so the tax is $2,167.50, 10.84% of the gain. Held a year or less, the same gain would cost $3,750.00 at ordinary rates.
High incomes also pay the 3.8% Net Investment Income Tax on the smaller of the gain and the amount by which income exceeds $200,000 ($250,000 joint, $125,000 separate). A married couple with $400,000 of income and a $300,000 gain pays $47,705 of capital gains tax plus $11,400 of NIIT. Not included: state income tax, the 25% rate on depreciation recapture from real estate and the 28% rate on collectibles.
UK: 2026/27 rates
After the £3,000 allowance, gains are added on top of your taxable income (income minus the £12,570 Personal Allowance). The part that fits in the £37,700 basic rate band is taxed at 18% and the rest at 24%, for property and shares alike. Scottish taxpayers use the same UK band for gains.
Example (GOV.UK's own): taxable income £20,000, gains £52,600. Take off £3,000: £49,600 is taxable. £17,700 fits in the basic rate band (£37,700 − £20,000) at 18% and £31,900 is taxed at 24%: £10,842 in all.
Australia: the 50% discount and your marginal rate
A net capital gain is added to your taxable income. Residents who owned the asset for at least 12 months halve it first (50% CGT discount). 2026-27 rates: nothing up to $18,200, then 15% to $45,000, 30% to $135,000, 37% to $190,000, 45% above. In 2025-26 the 15% rate was 16%; the other rates and thresholds were the same. The calculator also applies the low income tax offset and, if you choose, the 2% Medicare levy.
Example: $90,000 taxable income and a $20,000 gain on shares held for two years, sold in 2026-27. The discount leaves $10,000, which is taxed at 30%: $3,000, plus $200 Medicare levy = $3,200, an effective 16% of the gain.
Tips
- Keep records of what you paid, including fees and improvements: they reduce the gain.
- Timing matters: holding past a year (US) or 12 months (Australia) can cut the tax, and in the UK each tax year has its own £3,000 allowance.
- Work out the return first with the ROI calculator. Selling crypto in India? Use the crypto tax calculator. For your salary, see the US and UK tax calculators.
Rates checked on 2 October 2026 against IRS Rev. Proc. 2025-32, IRS topics 409, 559 and 701, GOV.UK Capital Gains Tax rates and allowances and rates, the ATO's resident tax rates and CGT discount pages, and Treasury on the 2026-27 Budget. An estimate, not tax advice: check your own situation with a tax adviser or your tax authority.