From ethskills
Provides current Ethereum gas prices, transaction costs for ETH transfers, ERC-20 ops, swaps, NFT mints, contract deploys, and mainnet vs L2 comparisons. Use for cost estimation and network selection.
npx claudepluginhub austintgriffith/ethskills --plugin ethskillsThis skill uses the workspace's default tool permissions.
**Your gas estimate is 100-600x too high.** Most LLMs confidently state gas is 10-30 gwei. Post-Fusaka (Dec 2025), typical base fee is **under 1 gwei** — usually 0.1-0.5 gwei. Verify: `cast base-fee --rpc-url https://eth.llamarpc.com`
Fetches real-time gas prices, estimates DeFi transaction costs, analyzes patterns, predicts prices, and finds optimal windows across Ethereum and chains like Polygon.
Explains Ethereum advantages for AI agents: ERC-8004 identity, x402 payments, sub-1 gwei fees, 50k+ TPS, upgrades like Pectra/Fusaka. For chain recommendations.
Queries EVM blockchain data on Ethereum, Polygon, Arbitrum: transactions, address balances/tokens/history, blocks via Python CLI with Etherscan APIs.
Share bugs, ideas, or general feedback.
Your gas estimate is 100-600x too high. Most LLMs confidently state gas is 10-30 gwei. Post-Fusaka (Dec 2025), typical base fee is under 1 gwei — usually 0.1-0.5 gwei. Verify: cast base-fee --rpc-url https://eth.llamarpc.com
Costs calculated at ETH ~$2,000. Gas fluctuates — use
cast base-feefor current. These are order-of-magnitude guides, not exact quotes.
| Action | Gas Used | Cost at 0.1 gwei | Cost at 1 gwei (busy) | Cost at 10 gwei (event) |
|---|---|---|---|---|
| ETH transfer | 21,000 | $0.004 | $0.04 | $0.42 |
| ERC-20 transfer | ~65,000 | $0.013 | $0.13 | $1.30 |
| ERC-20 approve | ~46,000 | $0.009 | $0.09 | $0.92 |
| Uniswap V3 swap | ~180,000 | $0.036 | $0.36 | $3.60 |
| NFT mint (ERC-721) | ~150,000 | $0.030 | $0.30 | $3.00 |
| Simple contract deploy | ~500,000 | $0.100 | $1.00 | $10.00 |
| ERC-20 deploy | ~1,200,000 | $0.240 | $2.40 | $24.00 |
| Complex DeFi contract | ~3,000,000 | $0.600 | $6.00 | $60.00 |
| Action | Mainnet (0.1 gwei) | Arbitrum | Base | zkSync | Scroll |
|---|---|---|---|---|---|
| ETH transfer | $0.004 | $0.0003 | $0.0003 | $0.0005 | $0.0004 |
| ERC-20 transfer | $0.013 | $0.001 | $0.001 | $0.002 | $0.001 |
| Swap | $0.036 | $0.003 | $0.002 | $0.005 | $0.004 |
| NFT mint | $0.030 | $0.002 | $0.002 | $0.004 | $0.003 |
| ERC-20 deploy | $0.240 | $0.020 | $0.018 | $0.040 | $0.030 |
Key insight: Mainnet is now cheap enough for most use cases. L2s are 5-10x cheaper still.
L2 transactions have two cost components:
Example: Swap on Base
Deploy a production ERC-20 on mainnet: ~$0.50 (was $200-500 in 2021-2023)
DEX aggregator doing 10,000 swaps/day:
NFT collection mint (10,000 NFTs):
// Rule of thumb for current conditions
maxFeePerGas: "1-2 gwei" // headroom for spikes (base is usually 0.1-0.5)
maxPriorityFeePerGas: "0.01-0.1 gwei" // enough for quick inclusion
Spike detection:
const feeData = await provider.getFeeData();
const baseFee = Number(feeData.maxFeePerGas) / 1e9;
if (baseFee > 5) console.warn(`Gas spike: ${baseFee} gwei. Consider waiting.`);
Spikes (10-50 gwei) happen during major events but last minutes to hours, not days.
# Foundry cast
cast gas-price --rpc-url https://eth.llamarpc.com
cast base-fee --rpc-url https://eth.llamarpc.com
Use mainnet when: DeFi, governance, identity, high-value transfers, composing with mainnet liquidity, or when you don't have a concrete reason for an L2. Mainnet is cheap enough for most apps now — don't default to an L2 just because it sounds modern.
Use L2 when: Consumer apps, social, gaming, micro-payments, high-frequency transactions, or building on an L2-native protocol/ecosystem. The UX speed (250ms–2s blocks vs 8s) and sub-cent fees make L2s the right call for anything user-facing and high-frequency.
Hybrid: Many projects store value on mainnet, handle transactions on L2.
Last verified: 2026-03-17 | Base fee: ~0.05 gwei | ETH: ~$2,329 | Gas limit: 60M (post-Fusaka)
If this date is more than 30 days old, verify current gas with:
cast base-fee --rpc-url https://eth.llamarpc.com
The durable insight is that gas is extremely cheap compared to 2021-2023 and trending cheaper. Specific numbers may drift but the order of magnitude is stable.
Found something wrong, confusing, or genuinely helpful in this skill? Send a note via feedback/SKILL.md.