Blockchain
Gwei
A denomination of Ether equal to one billion wei (10^9 wei or 0.000000001 ETH). Gwei is commonly used to express gas prices on the Ethereum network.
Last updated: January 5, 2025
What is Gwei?
Gwei (gigawei) is a denomination of Ether used to express gas prices on Ethereum. One Gwei equals one billion wei, or 0.000000001 ETH. When you see gas prices quoted as “30 Gwei,” this is how much you pay per unit of gas for transaction processing.
Ethereum Denominations
| Unit | Wei | Gwei | ETH |
|---|---|---|---|
| Wei | 1 | 0.000000001 | 0.000000000000000001 |
| Gwei | 1,000,000,000 | 1 | 0.000000001 |
| Ether | 10^18 | 10^9 | 1 |
Why Gwei Exists
Practical Numbers
- Gas prices in wei would be huge numbers
- ETH would have many decimal places
- Gwei provides human-readable middle ground
Gas Price Context
- “30 Gwei” is easier than “30,000,000,000 wei”
- Or “0.00000003 ETH”
Understanding Gas Prices
Transaction Cost Formula
Total Fee = Gas Used × Gas Price (Gwei) × 0.000000001Example Calculation
- Gas used: 21,000 (simple transfer)
- Gas price: 30 Gwei
- Cost: 21,000 × 30 × 0.000000001 = 0.00063 ETH
At ETH = $2,000:
- USD Cost: ~$1.26
Current Gas Price Ranges
| Activity | Typical Gas | At 30 Gwei | At 100 Gwei |
|---|---|---|---|
| ETH transfer | 21,000 | $1.26 | $4.20 |
| ERC-20 transfer | 65,000 | $3.90 | $13.00 |
| Uniswap swap | 150,000 | $9.00 | $30.00 |
| NFT mint | 100,000+ | $6.00+ | $20.00+ |
Assumes ETH = $2,000
Gas Price Tiers
| Gwei Range | Speed | When to Use |
|---|---|---|
| Under 20 | Slow | Not urgent |
| 20-50 | Normal | Standard transactions |
| 50-100 | Fast | Time-sensitive |
| 100+ | Very fast | Urgent, high congestion |
Checking Gas Prices
Tools
- Etherscan Gas Tracker: Real-time prices
- Blocknative: Gas predictions
- Wallet estimates: Built into MetaMask, etc.
Best Times
- Weekends often cheaper
- Late night (US time) lower
- Avoid NFT drops and big events
Tips to Save on Gas
- Wait for low Gwei - Use gas trackers
- Set custom gas price - Don’t overpay
- Batch transactions - Combine when possible
- Use Layer 2 - Much cheaper than mainnet
- Time your transactions - Avoid peak hours
Gwei on Different Networks
While Gwei is specific to Ethereum, similar concepts exist:
- BNB Chain: Uses Gwei-equivalent
- Polygon: Very low Gwei prices
- Arbitrum/Optimism: Lower than mainnet
Trade and interact with Ethereum on exchanges like Coinbase and Kraken with built-in gas optimization.
Ready to Start Trading?
Now that you understand gwei, explore the best exchanges to begin your crypto journey.