Railgun Tracer

Putting money into Railgun is an ordinary transaction, so the address that deposited, the token and the amount are all public. Taking money out is public too: the receiving address, the token and the amount are written into the withdrawal. What Railgun hides is the path in between. This tool reads the deposits an address made, then pulls every withdrawal of the same token between the dates you picked.

Unlike Tornado, Railgun does not use fixed amounts, and that helps here. Railgun takes a small fee on the way in and again on the way out, but the withdrawal records both the amount sent and the fee taken. Add those two together and you get exactly what was spent from inside Railgun. If someone puts in a sum and later takes the whole of it out in one go, the numbers match to the last unit. Those rows are marked "exact" in the By amount tab. The By time tab shows the same withdrawals ordered by how soon they came after the deposit.

ETH goes in and out through a Railgun helper contract that wraps and unwraps it. When a withdrawal lands on that helper, the tool checks where the ETH went next and shows that address instead, with a small note under it.

• It only works from the deposit side. If you search an address that withdrew from Railgun, the page will tell you so, but it can't trace backwards to the deposit.
• Money can be swapped to another token inside Railgun before it comes out. The tool compares the same token only, so it misses those.
• Partial withdrawals and several deposits merged into one withdrawal will not match exactly. The By amount tab shows the percentage difference, so close ones still show up, but they mean less.
• Only Railgun on Ethereum mainnet is covered, from the November 2022 contract upgrade onwards. Railgun on Polygon, BNB Chain and Arbitrum is not included.
• Using Railgun is not a sign of wrongdoing on its own. Plenty of people use it for ordinary privacy. Treat every match as something to check against other evidence.