The method changes the tax, not the trade
Same coins, same sale, different reported gain — that is the FIFO vs LIFO effect. Picking the allowed method that fits your situation can defer tax. Estimate the bill with the crypto tax calculator and offset with tax-loss harvesting.
Which coins did you "sell"? Tax math cares
Sell part of a stack bought at multiple prices and your taxable gain depends on which lots you're deemed to have sold. FIFO (first-in-first-out) sells your oldest coins; LIFO your newest; specific identification lets you choose. Same sale, materially different tax bills.
Example: bought 1 BTC at $30k (2023) and 1 at $90k (2025); sell 1 at $100k. FIFO realizes a $70k gain; LIFO realizes $10k. If your jurisdiction taxes long-held assets at lower rates, FIFO's bigger gain might still tax less than LIFO's smaller one — the interaction between method and holding-period rules is where the real money hides.
Two practical notes: your jurisdiction dictates which methods are allowed (some mandate FIFO, some allow specific-ID with record-keeping requirements), and the method's benefit compounds with record quality — exchanges delete old data, so exporting complete trade history yearly is what keeps the favorable method available to you at all. Run both numbers before selling, not at filing time.