How is RAILGUN Different from a Mixer?

4 min readFeb 18, 2022


RAILGUN is not a Mixer. Not only is the RAILGUN Privacy System capable of so much more than what can be achieved by using a Mixer, the technological method to achieve privacy is very different and much more complete. Indeed, there are many advantages to using RAILGUN over a Mixer. Let’s investigate some of the differences.

What is a Mixer?

A Mixer, also called a Tumbler, is a privacy protocol that, for a fee, mixes tokens from a variety of sources together when sending them from A to B. This makes it difficult to ascertain where received tokens originated, as the final transaction is sent by the Mixer protocol rather than the sender, and the tokens are from multiple origins. In some cases, the user must trust the protocol with the funds they are sending, though most mixers are non-custodial through the use of smart contracts. Many mixers also require the sender and the recipient to be the same, simply breaking the clear link between the original tokens and the received tokens.

Scrambling funds from across different wallets makes it difficult to track whose money went where and in what amount. Difficult, but perhaps not impossible — as specialists and even commercial companies like Chainalysis and Nansen offer services that can often unscramble what tokens went to what addresses for the right price. While some mixers have been able to make this more challenging by greatly increasing their anonymity set — the number of users putting tokens in and taking tokens out — only a very limited number have an unlimited anonymity set like RAILGUN’s Privacy System. Even with these relatively high-quality mixers, users may encounter other problems that they will not when using RAILGUN.

What are the Problems with Mixers?

Even with a break in the chain of custody, certain user behaviors can make it very obvious whose funds are going to a particular destination if they are sending a very recognizable token quantity. If 4.191272114 ETH enters a mixer and 4.191272114 ETH leaves it, the connection between the transactions will be very clear.

For this reason, most mixers require fixed amounts for their transactions, with users forced to send tokens only in denominations like 1, 10, or 100. This means if you don’t have these exact amounts in your wallet, you may not be able to send what you want — and will potentially end up with wasted “change” left over. Even if you can subdivide your desired amount to fit these requirements, that will mean you have to transact multiple times to send everything, incurring extra gas fees.

Does RAILGUN Solve these Issues?

First of all, RAILGUN is not a Mixer and does not add tokens from different sources together, instead making transactions fully invisible through zk-SNARKs cryptography. RAILGUN works by “shielding” a user’s tokens within its Privacy System, so that every transaction appears on the blockchain as being sent from the RAILGUN contract address. With relayers, the gas fees also have no connection with the user, assuring privacy. Your trustless, immutable transactions within the system are completely invisible to outside observers — not just mixed.

While this means that the same problem exists — 4.191272114 ETH entering the system and 4.191272114 ETH leaving it — RAILGUN can be used in a manner that does not force users to transact in set amounts. Firstly, RAILGUN allows users to maintain a balance, meaning the full amount of ETH doesn’t need to exit the system at the same time — a portion could be sent, or it could be added to an existing balance, or even stay in the system an extended period of time. As long as users take a minimum level of precaution, their funds can leave the system without obviously being the same precise amount that went in. RAILGUN is also a comprehensively audited open-source smart contract, so there is no way for anyone other than the user to take custody of their tokens at any point in the process.

Not only does RAILGUN perform anonymous transfers of tokens with superior privacy to Mixers, it is capable of so much more.

What Else Can RAILGUN Offer?

The aforementioned ability to maintain a private balance is a huge step beyond what a mixer is capable of doing for a user. Being able to keep tokens within the RAILGUN Privacy System means you have privacy at rest — your balance and what you choose to do with it remains private once tokens are shielded, with no further input required. As your balances can change any number of times within the system, no outside observer can possibly know what you are holding.

And then of course, RAILGUN brings privacy to DeFi — not only can you maintain a private balance and send your tokens to other users completely privately, you can interact with DApps and other DeFi protocols while maintaining your privacy. With RAILGUN, users can hold a shielded balance in a variety of tokens and can directly interact with DeFi protocols anonymously, enabling private use of the whole world of Decentralized Finance. Mixers do not offer this kind of utility, nor make any claim to.

RAILGUN is not merely a new iteration of existing protocols, but the next giant leap forward in privacy technology.




Framework for ZK Privacy on EVM blockchains. Send transactions and interact with DeFi on Ethereum, Polygon, Arbitrum, and BSC privately.