Income Tax Calculator
Estimate annual income tax using a flat effective rate.
OpenCapital Gains Tax (CGT) Calculator
Estimate tax on gains after allowance and selected CGT rate.
Gain Before Allowance£0
Taxable Gain£0
Estimated CGT£0
About the Capital Gains Tax (CGT) Calculator
The Capital Gains Tax (CGT) Calculator is most useful when you want more than a quick number. Estimate capital gains tax after allowance and rate. In practice, that means turning a rough idea into a planning decision that you can actually live with month after month. A lot of people stop at the first result they see, but the real value of this tool comes from comparing scenarios and understanding why the result changes.
Next, change one input at a time. This is where many users miss the real insight. When you adjust several numbers together, it becomes hard to tell what is driving the change. A cleaner method is to hold everything constant except one variable. You might test testing the gain after allowances and estimated rates, then compare that result with the original scenario. That one comparison often teaches more than a dozen random calculations.
How to use the Capital Gains Tax (CGT) Calculator
- Enter income and tax settings as accurately as possible.
- Read the estimate as a planning figure rather than a final filing result.
- Use the output to judge after-tax impact before making a decision.
Capital gains estimate
Taxable gain = proceeds − cost basis − allowable costs − allowances; tax = taxable gain × applicable rate
- Proceeds: Sale value
- Cost basis: Original cost and allowable additions
- Allowances: Exempt amount or relief assumptions
CGT can depend on asset type, holding period, reliefs, and tax status, so treat this as an estimate for planning.
Quick planning notes for the Capital Gains Tax (CGT) Calculator
Estimate capital gains tax after allowance and rate. Start with a realistic baseline, then change one input at a time to see how the result moves. That makes it easier to compare scenarios and spot the trade-offs that matter most.
Tax planning notes
- Treat this as an educational estimate and verify official rates, thresholds, and allowances before filing.
- Run scenarios at different income levels to understand how rate changes affect net outcomes.
- Use salary and retirement tools alongside tax estimates to see the practical impact on take-home pay.
Keep in mind
These results are designed for educational planning. Real-world figures can change based on official rates, lender fees, tax treatment, insurance, and personal circumstances.
More pages related to this topic
Frequently asked questions
How accurate is this Capital Gains Tax (CGT) Calculator?
This tool is useful for planning and comparison. It uses simplified assumptions, so confirm important decisions with official rates, lenders, or tax advisers.
Can I use this Capital Gains Tax (CGT) Calculator on mobile?
Yes. The calculator is responsive and works on phones, tablets, and desktop browsers.
Does this tool store my financial data?
No. Calculator inputs stay in your browser and are not saved to our server.
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