Demystifying Ethereum gas fees. Learn what gas is, how it works, and how to save money on transactions.
fundamentalsBeginner10-15 minutes6 stepsPrerequisites: Basic understanding of Ethereum, MetaMask installed
On this page
Quick Overview
1Check Current Gas Prices
2Understand Gas Estimates
3Time Your Transactions
4Adjust Gas in MetaMask
5Consider L2 Networks
6Monitor Transaction
Gas fees are the cost of doing anything on Ethereum. Every transaction, swap, or smart contract interaction requires gas. Understanding gas helps you save money and time transactions better.
What is Gas?
Gas measures computational work on Ethereum. More complex operations need more gas. You pay for gas in ETH.
Gas Components:
Gas Limit: Maximum gas for transaction
Gas Price: Cost per gas unit (gwei)
Total Fee: Gas used x Gas price
Why Fees Fluctuate
Network demand drives prices:
High demand = expensive
Low demand = cheap
Peak: US/EU business hours
Cheap: Weekends, late night
Current Fee Landscape
Network
Typical Fee
Speed
. . . . -
. . . . . . -
. . . -
Ethereum
$5-50
15 sec
Arbitrum
$0.10-0.50
2 sec
Base
$0.01-0.10
2 sec
Polygon
$0.01-0.05
2 sec
Saving on Gas
Use L2 networks
Time transactions for low activity
Set custom gas limits
Batch transactions when possible
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Track gas across all chains with Fensory. Know before you transact.
Start Tracking →
Step-by-Step Instructions
1
Check Current Gas Prices
Visit etherscan.io/gastracker to see current Ethereum gas prices in real-time.
Tips
✓Prices shown in gwei (1 gwei = 0.000000001 ETH)
✓Lower is better
2
Understand Gas Estimates
When you transact, MetaMask shows estimated fee. This is gas limit times gas price.
Tips
✓Estimate can be lower than actual
✓Unused gas is refunded
3
Time Your Transactions
Check gas prices before transacting. Wait for lower prices if not urgent.
Tips
✓Weekends are usually cheapest
✓Use gas tracker alerts
4
Adjust Gas in MetaMask
Click Edit on gas estimate to customize. Advanced users can set custom gas.
Warnings
⚠Too low gas = stuck transaction
⚠Start with suggested values
5
Consider L2 Networks
For most DeFi, use Arbitrum or Base instead of Ethereum mainnet.
Tips
✓Same security, 10-100x cheaper
✓Most major protocols are on L2s
6
Monitor Transaction
After sending, watch on block explorer. Speed up stuck transactions if needed.