Gas Killer
Gas AnalyzerDocsBlogGitHubX / TwitterTelegram

Private ETH · settled by Gas Killer

Sepolia testnet

Private ETH, for less gas

Shield ETH, pay anyone privately, and take out any part. Who you pay and how much stay hidden. Every transaction carries a zero-knowledge proof, and checking it on chain is most of the 640–860k gas each one costs. Here Gas Killer's operators check it off chain instead, so shields, sends, withdrawals and take-ins all cost 26–38% less.

Get Sepolia ETH ↗ RAILGUN case study ↗ Inspired by anon.wei ↗
Your private wallet

This page needs a browser from 2022 or later. Update yours or use another.

Activity

Gas per transaction

Proved here

What happens when you click

  1. 01

    Prove

    Your browser proves the payment with Tacit's ceremony key: that you own the notes you spend and that the amounts add up. Your key never leaves this tab.

  2. 02

    Request

    The demo asks the Gas Killer router to run the pool's transact() on that proof. A take-in runs the router's sweep instead, which also opens your deposit box.

  3. 03

    Check off chain

    Gas Killer's operators each run the real contract code, proof check included, against Sepolia state, and sign the storage diff it produces.

  4. 04

    Verify and write

    One verifyAndUpdate checks the operators' quorum signature and writes the diff: new notes, spent markers and the new root. The proof's pairing check never runs on chain.

Account

Choose a wallet

Endpoints

Sign in to Gas Killer

Shielding, sending, withdrawing and taking in through Gas Killer need a free Gas Killer account, as the Game of Life demo does. Gas Killer's relayer pays the gas for sends, withdrawals and take-ins.

Sign in

No account yet? Sign up.

How does it stay private?

You shield ETH into a pool, and it becomes notes that only your key can open. You can pay anyone else in the pool, or take ETH back out to any address, and nothing on chain links the two ends.

The proof

Every transaction carries a zero-knowledge proof, made in your browser, that you own the notes you spend and that the amounts add up. The pool records new notes and spent-note markers, never who paid whom or how much. Your key never leaves this tab.

What Gas Killer sees

The same transaction that would otherwise go on chain: the proof and its public inputs. No keys, no note contents, nothing the chain wouldn't show. Its operators check the proof and sign what the pool should write, and the pool writes exactly that.

What shows on chain

Shielding shows the wallet and amount going in, and withdrawing shows the address and amount coming out, as with any private pool. Private payments between notes show neither.

Inspired by anon.wei ↗

What is Gas Killer?

Gas Killer makes smart contracts cheaper to run without rewriting them. Gas Killer's operators simulate a transaction off chain and write back only the storage changes it produces. On chain, the contract checks one aggregate signature from the operators and applies those changes, so heavy computation turns into a single signature check.

On this pool

The heavy part of every Tacit transaction is checking its zero-knowledge proof, about 254k gas of pairing math. Gas Killer's operators run that check off chain, so a shield, send, withdrawal or take-in costs 26–38% less. The pool gained one import and one modifier; its proofs, notes and wallet are Tacit's own.

Why teams use it

Other privacy apps

Proof checks are what make private payments expensive, and that's the part Gas Killer takes off chain. Against 400 historical RAILGUN transactions, Gas Killer saved 40.9% on shields and 53.9% on transacts. Read the case study ↗

Read the docs →Game of Life demo →