BeCuriouzLearn something new every day
Your crypto payment is never 100% "done" — just increasingly hard to undo
💡 On most blockchains a transaction is never absolutely final — it just becomes exponentially more expensive to reverse the deeper it's buried.
When a Bitcoin transaction lands in a block, it looks settled — but on most blockchains nothing is ever permanently final. This is probabilistic finality. Because a miner could in principle build a longer competing chain and overwrite recent history (a reorg), a freshly mined transaction can still be reversed. What makes it practically irreversible is depth: each new block stacked on top is another confirmation, and rewriting a buried transaction means out-mining the whole network for every block since.
That's why users wait for the customary 6 confirmations on large payments — the cost of reversal climbs exponentially with depth. Some newer designs chase deterministic finality: Ethereum's proof-of-stake adds checkpoints validators agree to finalize, after which reverting would require destroying huge staked value through slashing.
So "confirmed" is really a confidence level, not a guarantee. The deeper a transaction sits — or the more value pledged against reversing it — the closer to final it gets.