Tax rules differ by country, but many tax authorities share a few core ideas. This page describes them in general terms and is not tax advice.
In the United States, for example, the IRS has treated virtual currency as property since 2014. That means gains and losses are calculated much like those on shares: the difference between what you paid (cost basis) and what you received.
Save the date, amount, value in your local currency and purpose of every transaction. Exchanges and wallets may close or change; your own records remain.
Planning to use crypto towards a house? Read crypto and home down payments.
Educational content. Not investment advice.