Know your capital gains tax in seconds

Gainsy helps UK investors calculate CGT on stocks, shares, and options. No spreadsheets, no guesswork

  • Built for UK tax rules
  • Supports stocks, shares & options
  • Supports option selling, assignment & exercise
App screenshot

Capital gains tax shouldn't be this confusing

  • Figuring out CGT across multiple trades is a nightmare
  • Spreadsheets break the moment things get complex
  • Options and tax rules make it worse
  • You don’t know what you owe until it’s too late
Gainsy fixes this.

From trades to tax in 3 steps

1
Import or add your trades

Manual entry or broker import

2
We apply UK CGT rules automatically

Bed & breakfasting, stock splits and more

3
See exactly what you owe

Clear breakdown, no jargon

Everything you need to stay on top of CGT

Accurate calculations

Always up to date with UK tax rules

Built for investors

Stocks, shares, and options handled properly

No spreadsheets

Clean, simple interface anyone can use

Tax confidence

Know your position before filing your return

Your capital gains, at a glance

Dashboard view
CGT Preview

Why investors choose Gainsy

Designed with input from active traders Based on HMRC rules
Gainsy Spreadsheets
Automatic CGT rules Manual formulas
Handles complex trades Breaks easily
Clear outputs Confusing
Built for UK tax Generic
Automatic USD to GBP conversion
Stock splits
Handles option assignment

Simple, transparent pricing

No hidden fees.

View Pricing

Frequently Asked Questions

Yes, Gainsy is designed for UK tax rules and produces HMRC-compliant calculations.

Yes, Gainsy supports stocks, shares, and options (including assignment and exercise) for CGT calculations.

No, you can add trades manually or import them Via a CSV file.

Yes, Gainsy provides the breakdowns and reports you need for your self-assessment tax return.

Stop guessing your capital gains tax

Start using Gainsy for free