What is proof of reserves?
Quick Answer
Proof of reserves is a public attestation that an exchange actually holds the crypto it owes customers, usually via published wallet addresses and a Merkle tree letting you verify your own balance is included.
TL;DR
It proves assets exist — but without proving liabilities too, it's only half the picture.
Key Takeaways
- 1Born from the FTX collapse, where customer funds were secretly lent out
- 2Merkle proofs let you verify your balance is in the snapshot
- 3It shows assets but rarely proves total liabilities or debts
- 4Treat it as one trust signal, not a guarantee
Full Explanation
After FTX collapsed in 2022 — having quietly lent out customer deposits — exchanges raced to publish proof of reserves: cryptographic snapshots showing wallets they control and the balances inside. The better implementations add a Merkle tree of all customer balances, so you can check that your account was counted in the total.
The honest limitation: proving you hold 100,000 BTC means little if you secretly owe 150,000. A complete picture requires proof of liabilities too, which is harder to demonstrate and where most published schemes are weakest. Reserves can also be borrowed for the snapshot date and returned after.
How to use it as a customer: prefer exchanges that publish regular (monthly), third-party-verified reports with liability attestations and per-user Merkle verification — and still follow the golden rule that an exchange is for trading, not storage. Proof of reserves raised the industry's floor; it didn't remove the need for self-custody of long-term holdings.