- Duplicating a Bitcoin private key is nearly impossible, with odds of 1 in 1.4 quindecillion due to cryptographic complexity.
- Advanced quantum computing could pose future risks to blockchain security, but solutions such as quantum-resistant algorithms are being developed
The slogan “Not your keys, not your coins” has become a cryptocurrency industry standard, emphasizing the critical role of private keys in securing Bitcoin ownership.
The apparently arbitrary creation of wallet addresses, however, raises an interesting question: Is it possible for one user to create an exactly identical wallet address and private key as another user? Let’s examine the facts, odds, and technological safeguards that almost certainly prevent this, based on a CoinGecko video.
The role of private keys in blockchain security
Created with a blockchain address, the private key is a sophisticated alphabetic string. Access and authorization of transactions from the linked address requires this key. It serves as a special password, which only gives access to the contents of the wallet. Private keys, to be clear, are not like seed phrases.
The initial phrase acts as a master key, unlocking several addresses, such as access to an entire collection of mailboxes, while private key unlocks a specific address—much like a key to a mailbox.
No Duplicate Bitcoin Wallet Addresses
Wallet addresses and corresponding private keys are generated randomly; therefore, in theory, two users can produce exactly the same credentials.
However, the chances of this happening are astronomically small. Out of 2^160, the total number of possible Bitcoin wallet addresses is 1 in 1.4 quindecillion — a value denoted by 14 followed by 47 zeros. This degree of randomness guarantees that the probability of repeating an address is so low that it can be considered essentially impossible.
It would take about 137 quadrillion years to reach even a 50% chance of colliding with an existing address, even if one were to use a hypercomputer capable of producing a billion addresses every hour. For perspective, that’s a period far longer than the 13.8 billion year age of the universe.
Almost impossible to target funded Bitcoin wallet
The odds are only slightly better for a malicious actor who wants to create a private key that matches a wallet with real funds. Chainalysis estimates that as of 2018, there were approximately 172 million Bitcoin addresses with possible monetary capacity.
But most of them, 147 million, belonged to companies like exchanges and businesses that often use multi-signature wallets, which require several private keys to access. Only 25 million addresses associated with individual Bitcoin holders remain.
The odds of producing a private key that matches one of these funded wallets is 1 in 5.8 non-millions when considering the total number imaginable wallet address—more than 1.4 trillion.
It is estimated that it would take 667 quadrillion years to find a single matching address even with increased computing power — that of a hypercomputer that processes a billion addresses every hour. This calculation ignores the outrageous hardware, storage and power costs required to run such a system.
Quantum computing and the future of bitcoin security
Although private key duplication makes stealing Bitcoins nearly impossible with current technology, development quantum computing increases the possible threat to blockchain security.
With their massive computing capabilities, quantum computers can theoretically break cryptographic systems significantly faster than traditional computers. To proactively tackle this threat, the Bitcoin network and other blockchain systems are aggressively researching and creating quantum-resistant algorithms.
Like most Bitcoin wallets globally, the 100 BTC jackpot famously associated with one of Satoshi Nakamoto’s early wallets is certainly out of reach. The improbability of creating duplicate private keys guarantees that Bitcoin will remain secure within the current technological paradigm.
Even so, the blockchain community must be cautious and aggressive in changing its cryptographic protections as quantum computing evolves. Right now, Bitcoin owners can relax knowing their holdings are likely safe from illegal access.
