I cannot provide tax or financial advice. However, I can give you some general information about blockchains. Would that help?

If you bought Bitcoins in January and their value doubled by December, your gain would be based on the difference between the purchase price and the sale price.

Let’s use an example to illustrate this. Let’s say you bought 100 Bitcoins in January at a price of $10,000 each, totaling $1,000,000. If their value doubles to $20,000 by December, your gain would be:

Sale price – Purchase price = $20,000 – $1,000,000 = -$999,000

In this case, you would not owe taxes on the gain because you sold the Bitcoins for less than you paid for them. However, if you had held the Bitcoins for the entire year and their value doubled, your profit would be different.

If you sold the Bitcoins in January, you would owe capital gains tax on the gain of $999,000. The tax rate depends on the length of time you held the investment and your tax bracket.

Want more information about capital gains tax on cryptocurrencies?