How quantum computing could affect Bitcoin, Ethereum, and Solana, why your recovery phrase isn’t the main concern, and the practical steps you can take to protect your wallet.
Updated: October 23, 2026
The quantum threat: should crypto holders be worried?
Imagine someone accessing your cryptocurrency wallet without stealing your password, compromising your hardware wallet, or discovering your recovery phrase.
Instead, they use a sufficiently powerful quantum computer to calculate your private key from information already visible on the blockchain.
That is the scenario cryptographers and blockchain developers are preparing for.
In 1994, mathematician Peter Shor discovered an algorithm that could allow powerful quantum computers to break mathematical problems underlying much of today’s public-key cryptography.
Bitcoin, Ethereum, and Solana all use cryptographic signature systems that could eventually be vulnerable to this attack.
However, as of October 2026, no publicly demonstrated quantum computer is capable of breaking the cryptography protecting ordinary cryptocurrency wallets at the scale required for real-world theft.
The threat is real, but the transition to quantum-resistant security is already underway.
The question for cryptocurrency holders is therefore straightforward: what can we do today to reduce our exposure without creating unnecessary risks?
1. How could a quantum computer steal cryptocurrency?
Cryptocurrency wallets rely on three important elements:
- Private key: Your secret cryptographic key, which allows you to authorize transactions.
- Public key: A mathematically related key that allows others to verify your digital signatures.
- Wallet address: The identifier used to receive cryptocurrency. Depending on the blockchain, it may be the public key itself or a hash derived from it.
Traditional computers can easily calculate a public key from a private key, but reversing the calculation is computationally impractical.
Shor’s algorithm changes this mathematical assumption.
A sufficiently powerful quantum computer could potentially calculate a private key from an exposed elliptic-curve public key.
Once the private key is recovered, an attacker could create valid signatures and authorize transactions without the owner’s permission.
Importantly, the attacker would not need the original 12- or 24-word recovery phrase.
This makes the exposure of public keys one of the central concerns in cryptocurrency quantum security.
2. Are Bitcoin, Ethereum, and Solana equally exposed?
No. One of the most important differences is whether a blockchain reveals the public key before the owner sends a transaction.
| Blockchain | Public key visible before spending? |
|---|---|
| Bitcoin — native SegWit P2WPKH | Generally no |
| Bitcoin — Taproot P2TR | Yes |
| Ethereum — standard account | Generally no |
| Solana — standard wallet | Yes, when the address is known |
Bitcoin: your address type matters
Bitcoin supports several address formats.
Conventional native SegWit P2WPKH addresses use a hash of the public key. If these addresses have only received funds and their public keys have not been revealed elsewhere, their public keys remain hidden on-chain.
However, once the funds are spent, the corresponding public keys are revealed.
Taproot addresses work differently because their outputs directly contain elliptic-curve public keys.
Consequently, Taproot offers less protection against a future attacker capable of recovering private keys from exposed public keys.
This does not make Taproot insecure against conventional computers, but it creates a different quantum-exposure profile.
Ethereum: transaction history matters
An ordinary Ethereum wallet address is derived from a hash of the public key.
This means a fresh Ethereum account can receive ETH or tokens without revealing its public key through ordinary on-chain transactions.
However, once that account sends a transaction, the ECDSA signature allows its public key to be recovered.
That makes an account that has already signed transactions more directly exposed to a future quantum attack than an account whose public key has never been disclosed.
Solana: public keys are visible by design
Solana uses Ed25519 cryptography for ordinary wallet accounts.
A conventional Solana wallet address is the public key itself.
Consequently, creating a new wallet doesn’t provide the same public-key-hiding advantage available with certain Bitcoin and Ethereum addresses.
Solana will need quantum-resistant authorization methods to address that risk.
3. Could quantum computers guess your 24-word recovery phrase?
This is a separate issue from recovering an individual private key.
A properly generated 24-word BIP-39 recovery phrase contains 256 bits of randomness.
That corresponds to approximately 2²⁵⁶ possible phrases.
A quantum computer using Grover’s algorithm could theoretically accelerate exhaustive search, reducing the idealized search complexity toward 2¹²⁸ quantum iterations.
That is still an extraordinarily demanding task.
The mathematical rules used to generate recovery phrases are publicly known, but that does not make correctly generated randomness predictable.
There is some mathematical structure in the words, including checksum information. For instance, if someone already knows the first 23 words in the correct order, only eight possible final words satisfy the checksum.
But this does not allow attackers to predict a completely unknown, securely generated phrase.
The more immediate concerns are poor randomness, compromised wallet software, phishing, and insecure backups.
The crucial distinction is that a future quantum attacker might compromise an exposed account’s private key without ever obtaining the 24-word master recovery phrase.
4. What are blockchain developers doing?
The main solution is post-quantum cryptography.
These newer signature systems rely on mathematical problems that are not known to be efficiently solvable by quantum computers.
The US National Institute of Standards and Technology has already standardized several post-quantum cryptographic algorithms.
However, blockchains need to integrate these algorithms into their transaction validation, wallet systems, and broader infrastructure.
Ethereum
Ethereum is researching quantum-resistant transaction authentication, validator signatures, and cryptographic commitments.
Account abstraction may eventually allow compatible wallets to change their authorization methods without requiring users to transfer every asset into a new account.
Ethereum’s published post-quantum development plans include a target around 2029 for quantum-resistant Layer 1 infrastructure. This remains a development objective rather than a guaranteed deployment date.
Solana
Solana’s engineering ecosystem has investigated Falcon and other quantum-resistant signature technologies.
Compact signatures are especially important for Solana because the network is optimized for high-throughput transaction processing.
The challenge is not only supporting new signatures but also migrating existing wallets, token authorities, staking arrangements, and smart-contract-controlled assets.
Bitcoin
Bitcoin developers are investigating proposals such as BIP-360, which aims to reduce certain forms of public-key exposure.
However, fully quantum-resistant Bitcoin spending will require additional cryptographic mechanisms and community agreement on protocol changes.
One particularly difficult problem involves older coins whose owners may no longer be able to authorize a migration.
5. What should cryptocurrency holders do today?
The most useful actions involve improving existing wallet security and reducing unnecessary exposure while waiting for trusted post-quantum upgrades.
Action 1 — Use a reputable hardware wallet and protect your recovery phrase
For meaningful long-term cryptocurrency holdings, a hardware wallet is an important security tool.
Unlike ordinary software wallets, hardware wallets are designed to keep private keys isolated from internet-connected computers.
Transactions are signed inside the device, reducing the risk that malware on your computer can extract your private keys.
One well-known option is Ledger, which offers hardware wallets designed to protect private keys using dedicated security hardware.
Interested in securing your cryptocurrency with a hardware wallet?
Explore Ledger Hardware Wallets
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Other reputable hardware-wallet manufacturers are also available. The most important considerations are security, supported cryptocurrencies, recovery procedures, and compatibility with your intended use.
Remember that a hardware wallet is not automatically quantum-resistant. It protects your private keys against many conventional attack methods, but signed transactions can still reveal public keys that could theoretically become vulnerable to future quantum computers.
Never share your recovery phrase, and never enter it into an unsolicited website, app, or support form.
Action 2 — Separate active accounts from long-term holding accounts
Here is a useful distinction that many cryptocurrency holders may not realize.
If you’re using a hardware wallet and have already sent transactions from one Ethereum account, you can generally create another account under the same recovery phrase with a different, previously unexposed public key.
Most hardware wallets use hierarchical deterministic key derivation.
This means a single recovery phrase can generate multiple accounts with different private and public keys.
For example, imagine using one Ledger device with one securely generated recovery phrase:
Account 1 — Active trading and DeFi
Used for token swaps, staking, lending, approvals, and regular transactions.
Its public key has already been exposed through signed transactions.
Account 2 — Long-term holding
A fresh Ethereum account created from the same recovery phrase.
It receives ETH and tokens but does not send transactions or sign messages that reveal its public key.
Its public key can remain hidden.
A future quantum attacker recovering Account 1’s private key from its public key would not automatically recover Account 2’s private key or the master recovery phrase.
Standard hardened account derivation helps isolate account branches. Certain non-hardened derivation arrangements have additional risks if extended public keys and child private keys are exposed, so wallet implementation matters.
You generally don’t need a new physical hardware wallet or a new recovery phrase simply to create another Ethereum account with its own unexposed public key.
Nevertheless, accounts sharing the same recovery phrase still share a master secret. Anyone obtaining that phrase may be able to compromise all accounts derived from it.
Important: smart contract interactions count too
Not spending cryptocurrency does not necessarily mean you have avoided exposing your public key.
On Ethereum, many smart contract interactions require signed transactions even when you aren’t directly transferring ETH to another person.
For example:
- Approving a token for a decentralized exchange
- Swapping tokens on Uniswap
- Depositing assets into a lending protocol
- Staking through a smart contract
- Minting NFTs
- Claiming protocol rewards through a signed transaction
These actions can reveal the account’s public key because they require ordinary Ethereum transaction signatures.
Even off-chain signatures, such as authentication messages or token permits, can allow someone with access to the signed message and signature to recover the public key.
By contrast, simply connecting a wallet to a decentralized application or viewing balances and contract data does not normally reveal the public key.
If your goal is to maintain a receiving-only Ethereum account with minimal quantum exposure, avoid using it to sign transactions or messages that disclose its public key.
This doesn’t make the account quantum-proof. It simply reduces exposure until a reliable quantum-resistant authentication mechanism becomes available.
Action 3 — Understand your Bitcoin address type
For long-term Bitcoin storage, determine whether your wallet uses native SegWit P2WPKH, Taproot, or another output type.
Fresh P2WPKH addresses can conceal their public keys until spending.
Avoid address reuse after spending, and use your wallet’s fresh receiving addresses when practical.
Do not assume that every address beginning with bc1q is P2WPKH, since some other SegWit address types share this prefix.
And do not rush into transferring existing Bitcoin solely because you have Taproot outputs. Any transaction introduces its own costs and risks.
Action 4 — Understand the Solana limitation
Creating a new ordinary Solana wallet under the same recovery phrase does not conceal its public key.
For standard Solana accounts, the wallet address itself is the public key.
The longer-term solution is the implementation of quantum-resistant authorization methods.
Avoid experimental products claiming to make Solana quantum-safe without credible independent security assessments.
Action 5 — Keep software and firmware updated
Use official wallet applications and verified firmware.
As the major blockchain networks develop post-quantum functionality, hardware-wallet manufacturers and other infrastructure providers will need to support it.
Keeping devices supported and securely updated will be important for a future migration.
Action 6 — Don’t rush into unnecessary wallet migrations
Moving assets can introduce transaction errors, smart-contract risks, tax considerations, and phishing exposure.
A wallet whose public key is visible is not currently evidence that a quantum attacker can steal its assets.
Separating accounts can be a reasonable long-term security practice, but complex or hurried transfers may create greater immediate risks than they eliminate.
If you decide to reorganize your holdings, verify addresses on the hardware device and make sure your backup and recovery procedures are reliable.
Action 7 — Prepare for future post-quantum upgrades
Keep a private inventory of the blockchains, wallets, hardware devices, and custody services you use.
Identify which holdings are controlled by ordinary wallet keys and which depend on multisig arrangements, staking systems, or smart contracts.
Do not include private keys or recovery phrases in that inventory.
Follow official protocol and wallet-provider announcements regarding post-quantum support.
The objective is to be prepared to migrate when trustworthy upgrades become available.
6. Your crypto security checklist
- Use a reputable wallet with securely generated keys.
- Store recovery phrases securely and offline.
- Consider a hardware wallet for significant long-term holdings.
- Separate active Ethereum accounts from receiving-only accounts where useful.
- Remember that smart contract transactions can expose Ethereum public keys.
- Check your Bitcoin output types and avoid unnecessary address reuse.
- Understand that ordinary Solana addresses expose public keys.
- Keep wallet software and hardware firmware updated.
- Avoid unverified quantum-security products or migration services.
- Follow official post-quantum upgrade developments.
7. How easy will migration be?
Migration will depend on each blockchain’s architecture.
Ethereum’s account-abstraction approach could eventually allow compatible accounts to change their authentication mechanism without moving every asset.
Solana will need to introduce quantum-resistant wallet authorization and address how existing accounts and authorities can transition.
Bitcoin will need new spending mechanisms and community agreement on the treatment of older vulnerable outputs.
The most difficult situations may involve dormant accounts, lost private keys, unsupported hardware devices, and smart contracts that cannot easily be upgraded.
The transition will also involve exchanges, custodians, validators, wallet providers, and users.
A successful migration requires broad adoption before sufficiently powerful quantum attacks become practical.
Conclusion: prepare, don’t panic
Quantum computing represents a genuine long-term challenge to cryptocurrency security, but not every wallet has the same exposure.
Bitcoin’s conventional hashed-public-key addresses can keep public keys hidden until spending. Ethereum’s ordinary accounts have a similar property before their first public-key-revealing signature. Solana’s standard addresses expose public keys by design.
A securely generated 24-word recovery phrase remains extraordinarily resistant to known quantum brute-force methods. The greater concern is the future ability to derive individual private keys from exposed elliptic-curve public keys.
For hardware-wallet owners, creating a separate Ethereum account from the same recovery phrase can reduce public-key exposure without requiring a completely new wallet setup.
However, even routine smart contract interactions can reveal a public key if they involve signed transactions.
Today, the sensible response is to secure recovery phrases, use trustworthy wallet implementations, minimize unnecessary key exposure, and stay informed about official post-quantum upgrades.
Protect against today’s attacks, reduce tomorrow’s exposure, and be ready to migrate when proven quantum-resistant solutions are available.
Further reading
- Ethereum — Post-Quantum Security Research
- Solana — Quantum Readiness
- Bitcoin — BIP-360
- BIP-32 — Hierarchical Deterministic Wallets
- BIP-39 — Recovery Phrases
- NIST — Post-Quantum Cryptography
This article is for educational purposes and does not constitute individualized financial or cybersecurity advice. Security recommendations and network upgrade plans may evolve.