Zero Gas Fees
SKALE Chains on Ethereum operate with zero gas fees by default. The native gas token (sFUEL) has no monetary value and cannot be traded. It exists purely for EVM compatibility — wallets and tools see a gas token, but users never pay real money for transactions.
Who pays: sChain Owner
Key Points
- No monetary value — sFUEL cannot be purchased or sold
- EVM compatible — Works with MetaMask, Ethers.js, Foundry, etc.
- Spam prevention — Computational requirements still prevent abuse
- Zero gas fees — Users don’t pay for transactions on SKALE Ethereum chains
Gasless Transactions (Proof-of-Work)
Zero gas fee chains can optionally enable gasless transactions: users don’t even need sFUEL in their wallet. A Proof-of-Work algorithm generates a “magic number” that validates the transaction instead of a gas payment.
How It Works
- Client generates a random 256-bit magic number using PoW
- The magic number is used as the
gasPrice in the transaction
- Validators verify the computational work was performed
- No sFUEL balance required in the user’s wallet
When to Use
| Approach | Requires sFUEL | Best for |
|---|
| Zero Gas Fees | Yes (valueless) | Most applications |
| Gasless (PoW) | No | True decentralization, invisible UX |
Proof-of-Work is disabled by default on credit chains.
Gas Chains
A gas chain uses a real token (SKL, ETH, USDC, etc.) as the gas token. This works like a traditional L2 — users pay per-transaction in the chosen token. Gas chains are available on SKALE Expand deployments.
Who pays: Users
Comparison
| Feature | Zero Gas Fees | Gasless (PoW) | Gas Chain |
|---|
| Who pays | sChain Owner | sChain Owner | Users |
| Requires token? | sFUEL (valueless) | Nothing | Gas token (market value) |
| EVM compatible? | Yes | Yes | Yes |
| Best for | Most apps on SKALE Ethereum | Consumer UX | DeFi, financial |
