How Much ETH Do You Need for Gas? Swaps, Snipes and Rescues

By Merunas Grincalaitis, founder of MEV DAO and a developer who builds MEV, sniping and trading bots on Ethereum. Last updated: October 2026.

TL;DR: Multiply the gas an action uses by the gas price. A plain ETH transfer always uses 21,000 gas, a stablecoin transfer around 45,000 to 50,000, and a Uniswap swap usually 100,000 to 230,000. With mainnet base fees around 0.04 gwei on October 25, 2026, a swap cost about one cent. Gas prices move fast, though, so I keep enough ETH to cover a few actions at 5 to 20 gwei. For most wallets, 0.005 to 0.01 ETH is plenty for everyday use. Snipes and wallet rescues are different because the priority fee is what decides whether you land.

"How much ETH should I leave for gas?" is one of those questions where the internet gives you advice from 2021, when a swap could cost $50. Mainnet in late 2026 is much cheaper most of the time, but it still spikes. So instead of repeating guesses, I measured what common actions actually use and worked out the cost at different gas prices.

How are Ethereum gas fees calculated?

Your fee is the gas your transaction uses multiplied by the price per unit of gas. Since the London upgrade, that price has two parts, which ethereum.org's gas documentation lays out:

Base fee: set by the protocol for each block, and burned. It goes up when blocks are more than half full and down when they're less, by at most 12.5% per block.
Priority fee (tip): what you add on top to make block builders want your transaction.

So the formula is fee = gas used × (base fee + priority fee). Gas prices are quoted in gwei, and 1 gwei is 0.000000001 ETH (10^-9). The ethereum.org example is an ETH transfer at a 10 gwei base fee with a 2 gwei tip: 21,000 × 12 = 252,000 gwei, or 0.000252 ETH.

Two details trip people up. You set a maxFeePerGas, and the network refunds the difference between that and what the block actually charged. And if a transaction fails, you still pay for the gas it used up to the point where it reverted.

How much gas do common Ethereum transactions use?

I pulled every successful transaction from twelve consecutive mainnet blocks (26,270,189 to 26,270,200, on October 25, 2026) through a public RPC node and grouped them by what they did. These are medians from real transactions, not estimates from a calculator:

Action	Transactions seen	Median gas used	Range seen
ETH transfer	815	21,000	always 21,000
USDC transfer	206	45,160	40,324 to 62,718
USDT transfer	523	46,109	41,285 to 63,221
Other ERC-20 transfer	182	51,423	varies by token
ERC-20 approve	79	48,549	23,965 to 56,427
Uniswap swap (Universal Router)	20	122,242	97,639 to 226,525

A token transfer costs more than an ETH transfer because it runs contract code and writes to storage. Sending a token to an address that has never held it costs more than topping up an existing balance, which explains much of the spread. Swaps vary with the route: a single pool is cheap, a multi-hop route through several pools isn't.

How much does that cost in ETH?

Here's the same table priced at four gas levels. The first column is roughly where mainnet sat when I wrote this. The others are scenarios, not forecasts, so you can see what happens during busy periods. Dollar figures use $2,331 per ETH, the price shown on Etherscan's gas tracker at the time.

Action (median gas)	0.04 gwei	1 gwei	5 gwei	20 gwei
ETH transfer (21,000)	0.00000084 ETH (~$0.002)	0.000021 ETH (~$0.05)	0.000105 ETH (~$0.25)	0.00042 ETH (~$0.98)
USDT transfer (46,109)	0.0000018 ETH (~$0.004)	0.000046 ETH (~$0.11)	0.00023 ETH (~$0.54)	0.00092 ETH (~$2.15)
Approve (48,549)	0.0000019 ETH (~$0.005)	0.000049 ETH (~$0.11)	0.00024 ETH (~$0.57)	0.00097 ETH (~$2.26)
Uniswap swap (122,242)	0.0000049 ETH (~$0.01)	0.00012 ETH (~$0.29)	0.00061 ETH (~$1.43)	0.0024 ETH (~$5.70)
Heavy swap (226,525)	0.0000091 ETH (~$0.02)	0.00023 ETH (~$0.53)	0.0011 ETH (~$2.64)	0.0045 ETH (~$10.56)

For a cross-check, Etherscan's gas tracker showed 0.04 gwei for standard, fast and rapid when I looked, with a swap estimated at $0.033. That's a bit higher than my median because it includes a typical tip on top of the base fee.

To get a sense of how stable that is, I also queried eth_feeHistory for the last 1,024 blocks. The base fee ranged from 0.033 to 0.067 gwei, and the median tip was 0.01 gwei. Quiet, in other words. But quiet stretches don't last forever, and the 12.5% per block rule means fees can double in about six blocks, roughly a minute and a quarter, when demand surges.

How much ETH should you keep in your wallet for gas?

Enough to do the next few things you plan to do even if gas jumps. My own rule of thumb:

Everyday wallet: 0.005 ETH covers about 40 swaps at 1 gwei, or 8 at 5 gwei. If you want more room, 0.01 ETH doubles that.
Before a planned action: check the current base fee on a gas tracker or in your wallet, multiply by the gas from the table above, and keep at least 3 to 5 times that as a buffer.
Never empty a wallet down to zero ETH if it still holds tokens. Without ETH you can't move them, and you'll need someone to send you gas first.

That third point matters more than people think. A wallet full of tokens and no ETH can't do anything on mainnet. The token can't pay its own gas.

How much ETH do you need for gas when sniping?

More than for a normal swap, because sniping is a race. When a token launches, many bots try to buy in the same block, and builders order transactions largely by what each one pays them. The base fee is small in that equation. The priority fee, or the tip you attach to a private bundle, is what decides who lands first.

That's why I size gas for snipes per launch rather than per wallet. On a busy launch, the winning tips can be many times the base fee, and if the token has anti-snipe taxes or a blacklist you can pay a high tip and still lose money. I go deeper on tip sizing in sniper bot gas settings: priority fees and builder tips, and on how same-block buys work in block 0 sniper explained.

One practical point: keep the snipe budget and the gas buffer separate. If your sniper wallet holds exactly the ETH you want to spend on tokens, the first snipe will fail because nothing is left to pay for gas. Our Ethereum sniper bot sends buys as Flashbots bundles, so a snipe that would land in the wrong block or revert doesn't get included and doesn't burn gas.

How much ETH do you need to rescue tokens from a compromised wallet?

Here the answer is "exactly enough, delivered in the same bundle". If a sweeper bot is watching a hacked wallet, any ETH you send there gets swept out almost instantly. So a rescue usually works as a Flashbots bundle with three parts: a sponsor wallet sends just enough ETH to cover the rescue, the compromised wallet sends the tokens to a safe address, and both go into one bundle that lands together or not at all.

The gas math is the same as above. Moving two ERC-20 tokens might take about 100,000 gas for the transfers plus 21,000 for the sponsor's ETH transfer. The difference is the tip: builders get paid through the priority fee or a direct payment to the block's coinbase address, and the bundle has to be attractive enough to include. Getting that number wrong is the most common reason a rescue bundle never lands. I explain that in Flashbots bundles explained, and the full process is in how to rescue tokens from a compromised wallet with a sweeper bot.

Frequently asked questions

How much ETH do I need for gas fees?

It depends on the action and the current gas price. An ETH transfer uses 21,000 gas and a Uniswap swap usually 100,000 to 230,000. At late-2026 mainnet prices that's cents, but keeping 0.005 to 0.01 ETH gives you room when gas spikes.

Is 0.01 ETH enough for gas?

For normal use, yes. At 1 gwei, 0.01 ETH covers about 80 typical Uniswap swaps, and at 20 gwei still about 4. For competitive snipes or rescues, you may need more because the tip, not the base fee, decides inclusion.

Why is my gas fee so high?

Either the network is busy, which raises the base fee, or the transaction is complex and uses a lot of gas, like a multi-hop swap. Your wallet may also be showing the maximum fee you allow, and the difference gets refunded.

Do failed transactions cost gas?

Yes. A transaction that reverts still pays for the gas it used before failing. Private bundles avoid this because a bundle that would fail is simply not included.

How much gas does a Uniswap swap use?

In the mainnet blocks I measured, swaps through Uniswap's Universal Router used a median of about 122,000 gas, with a range from about 98,000 to 227,000 depending on the route.

What is gwei in ETH?

One gwei is one billionth of an ETH, or 0.000000001 ETH. Gas prices are quoted in gwei, so 21,000 gas at 1 gwei costs 0.000021 ETH.

If you want to snipe without working out tips by hand, the MEV DAO sniper handles gas and bundles for you, and there's a 3-day free trial. If you're dealing with a sweeper bot instead, message me on Telegram.