Gas fees — the price of every action
Paul's Ethereum transaction fails, yet the fee is gone. Gas is fuel: you pay in SOL on Solana and ETH on Ethereum and Arbitrum. Three roads to one city: the Solana motorway, the Arbitrum night route and the Ethereum capital. A jam makes Ethereum pricey, and a failed attempt still spends the gas.
GasGasThe transaction fee on a blockchain. Solana: under $0.01. Ethereum mainnet: transfer ~$0.01, swap ~$0.03-0.30. Varies with network load.Read the lesson → is like fuel for a car. Every action on a blockchain network (a transfer, a swap, an LPLPLiquidity Provider — deposits tokens into a pool and earns a share of trading fees.Read the lesson → position) needs "fuel". Without it — nothing moves.
What is gas?
Every action on a blockchain network (a transaction) requires computational work. The network's validators (computers) do this work, and you pay them for it — the gas fee.
GasGasThe transaction fee on a blockchain. Solana: under $0.01. Ethereum mainnet: transfer ~$0.01, swap ~$0.03-0.30. Varies with network load.Read the lesson → fees are paid in the network's native currency:
- On the SolanaSolanaA fast blockchain (under 1s, gas under $0.01). Home to the Kamino, Orca and Meteora ecosystem.Read the lesson → network → paid in SOL SOL
- On the EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → network → paid in ETH ETH
- On the ArbitrumArbitrumAn Ethereum Layer 2 network. Cheaper and faster transactions than Ethereum mainnet.Read the lesson → network → paid in ETH ETH
Why do prices differ so much?
| Network | Typical transaction | Complex action (LP, swap) | Why? |
|---|---|---|---|
| Solana SOL | ~$0.001 | $0.001–$0.01 | Fast, efficient design |
| Arbitrum ETH | < $0.01 | $0.01–$0.05 | L2 rollup — cheap and steady |
| Ethereum mainnet ETH | ~$0.01 | $0.03–$0.30 | Price shifts with network load |
EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → mainnet has limited space in every block. It works like an auction: when a lot of people want to transact at once, whoever offers more gas gets processed first, and the price rises. After the 2024 "Dencun" upgrade (and the blob-capacity increases that followed), space grew considerably, so on a normal day EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → costs cents — it only gets expensive during short peak moments. Before a bigger operation, it's worth glancing at etherscan.io/gastracker.
Solana gas — why is it so cheap? SOL
SolanaSolanaA fast blockchain (under 1s, gas under $0.01). Home to the Kamino, Orca and Meteora ecosystem.Read the lesson →'s architecture lets it process hundreds of transactions per second at minimal cost:
| Component | Price |
|---|---|
| Base transaction fee | |
| Priority fee (for faster processing) | 0.00001–0.001 SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson → |
| Rent (creating a new account) | ~0.002 SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson → (one-time) |
Note: SolanaSolanaA fast blockchain (under 1s, gas under $0.01). Home to the Kamino, Orca and Meteora ecosystem.Read the lesson → has a "rent" system — creating a new token account requires a small deposit (~0.002 SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson →). That deposit is refunded when you close the account.
The Ethereum gas system ETH
EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → uses the EIP-1559 gas model (a fee mechanism standardized in 2021):
| Component | What it is |
|---|---|
| Base fee | The network-set base price (changes every block) |
| Priority fee (tip) | An extra fee to the validator for speed |
| Gas limit | The maximum amount of gas you agree to spend |
Formula: Transaction cost = (base fee + priority fee) × gas used
Typical gas usage values
| Action | Gas amount | Approximate cost |
|---|---|---|
| ETH transfer | 21,000 | ~$0.01 |
| ERC-20 token transfer | 65,000 | ~$0.01–0.03 |
| UniswapUniswapAn Ethereum concentrated-liquidity protocol (V3/V4). Its Solana counterpart is Orca.Read the lesson → swap | 150,000 | ~$0.03–0.10 |
| Opening an LPLPLiquidity Provider — deposits tokens into a pool and earns a share of trading fees.Read the lesson → position | 300,000+ | ~$0.10–0.30 |
The prices in the table are for normal network load. During heavy activity (a popular token launch, market panic) the base fee can temporarily jump tens of times over — so check etherscan.io/gastracker before a bigger operation.
ArbitrumArbitrumAn Ethereum Layer 2 network. Cheaper and faster transactions than Ethereum mainnet.Read the lesson → is an EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → L2 (a second-layer network, or "rollup"). It bundles up many transactions and sends them to EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → mainnet as a single batch. That's why ArbitrumArbitrumAn Ethereum Layer 2 network. Cheaper and faster transactions than Ethereum mainnet.Read the lesson →'s price stays low and steady (usually < $0.01–0.05) even when mainnet gas temporarily spikes.
Priority fees — faster means pricier
Solana priority fees SOL
When the network is congested (e.g., a popular NFTNFTNon-Fungible Token — a unique token. Uniswap V3 LP positions are NFTs. mint):
- You can add a priority fee to get processed faster
- Jupiter and other interfaces have a "Priority Fee" setting
- The "Medium" level is usually enough
Ethereum priority fees ETH
- MetaMaskMetaMaskAn Ethereum/EVM wallet. Used with Aave, Uniswap and Arbitrum.Read the lesson → lets you choose: Low / Market / Aggressive
- Low: cheaper, but can take several minutes or longer
- Market: standard speed, usually ~15–30 sec
- Aggressive: pricier, but usually lands in the next block (~15 sec)
What happens when you run out of gas?
| Situation | Result | What to do |
|---|---|---|
| Not enough gas to start a transaction | Transaction doesn't start | Top up your SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson →/ETH balance |
| GasGasThe transaction fee on a blockchain. Solana: under $0.01. Ethereum mainnet: transfer ~$0.01, swap ~$0.03-0.30. Varies with network load.Read the lesson → runs out mid-transaction (ETH) | Transaction fails, BUT gas is spent | The gas money is lost, but tokens don't change hands |
| Priority fee too low | Transaction gets stuck "pending" | Increase the fee or wait |
- Ethereum: a failed transaction still spends gas → check the gas tracker before acting and set a suitable gas limit — that way you only pay for what actually happens
- Not enough gas to start a transaction → keep a small reserve of the network's native coin (SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson →/ETH), and you'll never get stuck
- Priority fee too low — transaction "pending" → MetaMaskMetaMaskAn Ethereum/EVM wallet. Used with Aave, Uniswap and Arbitrum.Read the lesson →/Jupiter let you raise the fee any time, or you can just wait
Every one of these situations has a clear solution. It's not a trap — it's a set of parameters you control.
How much to keep in your gas reserve?
| Network | Minimum | Recommended | Why more |
|---|---|---|---|
| SolanaSolanaA fast blockchain (under 1s, gas under $0.01). Home to the Kamino, Orca and Meteora ecosystem.Read the lesson → SOL | 0.01 SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson → | 0.05 SOL | Rent + several transactions |
| EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → ETH | 0.001 ETH | 0.005 ETH | GasGasThe transaction fee on a blockchain. Solana: under $0.01. Ethereum mainnet: transfer ~$0.01, swap ~$0.03-0.30. Varies with network load.Read the lesson → can spike unexpectedly |
| ArbitrumArbitrumAn Ethereum Layer 2 network. Cheaper and faster transactions than Ethereum mainnet.Read the lesson → ETH | 0.0005 ETH | 0.002 ETH | Several transactions |
When withdrawing crypto from a CEXCEXCentralized Exchange — a centralized exchange (e.g. Nexo, Kraken, Binance). Requires KYC.Read the lesson → (NexoNexoA centralized exchange (CEX) for buying crypto with euros. Custodial — the exchange holds the keys.Read the lesson →, Kraken), leave a small gas reserve. Once that becomes a habit, doors open: you can freely move crypto, open an LPLPLiquidity Provider — deposits tokens into a pool and earns a share of trading fees.Read the lesson → position, or manage collateral at any time — with no "oh no, I can't afford the fee" moment.
Monitoring gas prices
Best time for transactions:
- EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → gas is usually cheap any time; calmest at night (UTC) and on weekends, while it temporarily rises during peak moments
- SolanaSolanaA fast blockchain (under 1s, gas under $0.01). Home to the Kamino, Orca and Meteora ecosystem.Read the lesson → gas is almost always equally cheap
Summary
| Solana SOL | Arbitrum ETH | Ethereum ETH | |
|---|---|---|---|
| Typical price | ~$0.001–0.01 | < $0.01–0.05 | $0.01–$0.30 |
| Paid in | SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson → | ETH | ETH |
| Speed | ~2 sec | ~2–8 sec | ~15 sec–1 min |
| Reserve | 0.05 SOLSOLSolana's native token. Used to pay gas and as collateral.Read the lesson → | 0.002 ETH | 0.005 ETH |
Key rules:
- Always keep a gas reserve
- For EthereumEthereumA blockchain with smart contracts. We use Aave (lending) and Uniswap (LP) on it.Read the lesson → operations, ArbitrumArbitrumAn Ethereum Layer 2 network. Cheaper and faster transactions than Ethereum mainnet.Read the lesson → remains a good choice — the price stays low and steady even when mainnet gas spikes
- A failed transaction on the ETH network — gas is still spent
- SolanaSolanaA fast blockchain (under 1s, gas under $0.01). Home to the Kamino, Orca and Meteora ecosystem.Read the lesson → — gas is practically free
Gas prices change daily, so the most important skill is learning to check them yourself. This task takes about 10 minutes — nothing to send, just observe.
This is an observation task — nothing to send or confirm. Remember the rule: never spend your entire gas reserve, or you won't be able to make any transaction.
This is learning, not investing — use only small amounts you treat as tuition.
You just read the gas tracker and saw the L2 vs. Solana difference with your own eyes — now network fees aren't a surprise, they're a predictable number you control.