Railgun Review 2026: ZK Privacy for Ethereum DeFi

Railgun is a privacy protocol for Ethereum and other EVM networks. DefiLlama describes it as securing privacy for DEX trading and lending, and as a smart contract system that gives zk-SNARK privacy to any transaction or smart contract interaction.

DefiLlama lists it in the Privacy category on Ethereum, Arbitrum, BNB Chain and Polygon, with roughly $113 million in TVL and two audits listed. It has been tracked since January 2022 and has its own token, RAIL.

The project says it is purely on-chain, with no KYC, no custody, no bridge and no central actors. It also says it has no in-house app and is made for third parties to build on, so most people will meet it through integrations. This review is based on public data and project statements, not hands-on testing.

Public blockchains show every address balance and transaction. Railgun adds a privacy layer on top using smart contracts and zk-SNARKs, a type of zero-knowledge proof that lets someone prove a transaction is valid without revealing who sent what.

Users deposit tokens into the Railgun contracts, often called shielding. Inside, balances and transfers are tracked privately. Users can then send funds or interact with DeFi protocols such as DEXs and lending from that private balance, and later withdraw to a public address.

The system runs as smart contracts directly on Ethereum, Arbitrum, Polygon and BNB Chain, with no bridge or layer-2 involved. It ships no consumer app of its own, so wallets and other apps are expected to build it in.

Fees are not published. They would likely appear in the wallet or app used to access Railgun, along with network gas costs on the chain used.

Public sources list a RAIL token with a Google snippet price of $2.17, but they do not describe protocol fees, staking rewards or any fee distribution. Check the official site and documentation for current figures before moving funds.

DefiLlama lists two audits, but the auditors, dates and findings are not public, so read the reports on the official site. As with any smart contract system, bugs in the contracts or zero-knowledge circuits are a risk, and funds held in the contracts are exposed to that risk.

The project says it is non-custodial with no central actors, so users hold their own keys and no one can recover lost access. No hacks or incidents are mentioned publicly, but absence of mention is not proof of none. Privacy tools are subject to evolving regulation, so check local rules before using it.

Railgun is for DeFi users, traders and developers on Ethereum, Arbitrum, Polygon or BNB Chain who want to keep balances and activity from being fully public, and who are comfortable using a protocol through wallets or integrations. It is less suited to people wanting a single app with support, or those unsure about the legal status of privacy tools where they live.