What is Zephyr Protocol?
Zephyr Protocol is a proof-of-work blockchain launched in 2023 that combines Monero-style privacy with a crypto-backed stablecoin design called Djed. Users can turn ZEPH into a private dollar-pegged coin, ZSD, which is backed by a reserve of ZEPH held by the protocol itself rather than by a company.
Utility Lens
What Zephyr Protocol actually does
Lets users hold and send a dollar-pegged stablecoin with the same privacy as Monero, without relying on a company that holds the backing.
- Real-world usage
- earlyThe private stablecoin works on mainnet, but ZSD supply and trading are small and centered on a few offshore exchanges.
- Token necessity
- essentialZEPH is the mined coin, pays fees and is the collateral that backs every ZSD in the reserve.
- Decentralization
- limitedMining uses CPU-friendly RandomX, but a small team controls development, the system leans on a price oracle, and the 2025 audit ended with a one-time mint of ZEPH for one exchange.
- Track record
- developingLaunched in 2023; a 2025 bug that let some transactions turn ZSD and ZRS into ZEPH forced a months-long chain-wide audit, and no core release has shipped since June 2025.
What it’s used for
Users mine ZEPH with CPUs, convert it into the ZSD stablecoin or the ZRS reserve share, and can stake ZSD for a share of block rewards through ZYS yield shares. All four assets move privately. Trading takes place on a handful of offshore exchanges such as MEXC, XT and CoinEx, and use of ZSD remains small.
Role of the ZEPH token:
Evidence of real use
- Version 2.0.0, activated at block 360,000, added the ZSD yield mechanism, which sends 5% of each block reward to ZSD stakers. Source (opens in a new tab)
- After finding a bug that let 30 transactions convert ZSD and ZRS into ZEPH, Zephyr ran a chain-wide audit that paused normal transfers from March to June 2025. Source (opens in a new tab)
- The latest core release on GitHub, v2.3.0, was published in June 2025. Source (opens in a new tab)
Privacy: what’s hidden, what isn’t
- Privacy model
- default (every transaction)
- What it hides
- Sender, receiver and amount for ZEPH, ZSD, ZRS and ZYS transfers.
- What stays visible
- Transaction timing and fees, plus protocol-wide totals such as the size of the reserve and the circulating supply of each asset.
- Reality check
- Zephyr's homepage calls the protocol "untraceable," but it relies on the same ring-based privacy as Monero, so senders are hidden within a ring rather than among all outputs. Its 2025 bug also showed that hidden amounts can mask supply problems until an on-chain audit is run.
How Zephyr Protocol works
Zephyr copies Monero's privacy tools, so ring signatures, stealth addresses and hidden amounts protect every transfer. On top of that it runs four native assets. ZEPH is the base coin, mined with RandomX every two minutes. ZSD is the stablecoin, meant to be worth one US dollar of ZEPH. ZRS is a reserve share that owns the leftover value in the reserve, and ZYS represents ZSD staked for yield.
The design follows Djed, a stablecoin model developed with input from the Ergo Foundation, Emurgo and IOHK. When someone mints ZSD, the ZEPH they pay goes into an on-chain reserve rather than to a company. Minting more ZSD is only allowed while that reserve is worth at least four times the ZSD in circulation, and new ZRS stops being minted above an 800% ratio. A price oracle supplies spot and moving-average ZEPH prices for these conversions.
Because the backing is ZEPH itself, a sharp drop in ZEPH's price shrinks the reserve. When the ratio falls below 400%, new ZSD cannot be minted and the price of ZRS falls, which is meant to tempt buyers to add ZEPH to the reserve. Since version 2.0.0, 30% of each block reward goes to the reserve and 5% feeds the ZSD yield pool, with miners keeping 65%.
Key moments
- 2023Zephyr's mainnet launches, followed by a MEXC listing and the V1 hard fork that adds ZSD and ZRS.
- 2024Version 2.0.0 activates at block 360,000 and introduces ZSD yield through ZYS shares.
- 2025A cross-asset bug triggers an emergency fork in January and a chain-wide audit that pauses normal transfers from March to June.
- 2025Version 2.3.0 restores normal operation in June with audited assets and a one-time mint of 1,921,650 ZEPH for MEXC; no core release has followed.
Supply
ZEPH was designed with an 18.4 million main supply plus a permanent tail emission of 0.6 ZEPH per block. After the 2025 audit, which raised the reported ZEPH supply by about 2.06 million, the team moved emission ahead to its end-of-year-three schedule and says the 18.4 million main cap still stands.
Risks to understand
- Development appears to have stalled: the latest core release on GitHub dates from June 2025.
- ZSD is backed only by ZEPH, so a steep fall in ZEPH's price can freeze new ZSD minting and test the peg.
- A 2025 consensus bug let some transactions convert ZSD and ZRS into ZEPH, and fixing it required freezing transfers and invalidating unaudited coins.
- Coinbase and Kraken do not offer ZEPH, trading is thin, and from July 10, 2027 EU-regulated providers may not handle anonymity-enhancing coins.
Zephyr Protocol FAQ
What is ZSD?
Zephyr's private stablecoin, meant to be worth one US dollar. It is backed by ZEPH held in an on-chain reserve rather than by cash in a bank.
What happened in Zephyr's 2025 audit?
The team found a bug that let 30 transactions turn ZSD and ZRS into ZEPH. It paused normal transfers, had every holder re-attest balances on-chain, and invalidated coins that were not audited.
Is Zephyr still being developed?
As of October 2026 the latest core software release on GitHub is v2.3.0, published in June 2025, which finished the chain audit.
Can I buy ZEPH in the US?
Not on major US platforms. As of October 2026 Coinbase and Kraken do not offer it.
Sources
- Zephyr Protocol whitepaper (opens in a new tab) — Zephyr Protocol
- Zephyr Protocol homepage and roadmap (opens in a new tab) — Zephyr Protocol
- Zephyr Protocol v2.0.0: ZSD yield announcement (opens in a new tab) — Zephyr Protocol
- Zephyr audit: postmortem (opens in a new tab) — Zephyr Protocol
- Zephyr Protocol v2.3.0: audit completion (opens in a new tab) — Zephyr Protocol (GitHub)
- Regulation (EU) 2024/1624 (Anti-Money Laundering Regulation) (opens in a new tab) — EUR-Lex, Official Journal of the EU
Last reviewed October 20, 2026. Written by Dave McNaught. Utility Lens ratings are editorial judgments, not investment advice. Market data from CoinGecko. Spot an error? Request a correction.
Dave McNaught
Dave McNaught has worked in IT since 1999 and founded All Business Technologies (ABT) in 2003, a Boston-area firm providing Managed IT, Cybersecurity, Managed AI, Web Design and App Development. He publishes The Crypto Guide.