What is slippage in a crypto swap?

Slippage is the difference between the price you were quoted when you clicked and the price your swap actually executed at. It happens because the blockchain takes time to confirm your transaction, and the pool can move in the meantime.

What is the difference between slippage and price impact?

Price impact is the part of the price move your own trade causes by consuming liquidity. Slippage is the total gap between quote and execution, which includes your price impact plus anything else that happens to the pool while your transaction is pending.

What slippage tolerance should I use?

For deep, liquid pairs like ETH/USDC, 0.1% to 0.5% is usually enough. Volatile or thin tokens may need 1% to 3%. Setting it very high does not get you a better price, it only raises the worst price you are willing to accept.

Why did my swap fail with a slippage error?

The price moved further than your tolerance allowed before the transaction confirmed, so the trade reverted to protect you. That is the setting doing its job. You can retry, or raise the tolerance slightly if the pair is volatile.

What Is Slippage in Crypto? Slippage vs Price Impact (2026)

You saw one number when you clicked, and a slightly different number landed in your wallet. That gap is slippage — and once you understand where it comes from, the setting in your swap screen stops being a mystery box you nudge until the trade goes through.

Slippage is the difference between the price you were quoted and the price your swap actually executed at. It exists because a blockchain trade isn't instant. You sign, your transaction waits to be included in a block, and during that wait — often just seconds — the pool you're trading against can move.

Two things cause that movement, and telling them apart is the whole game.

Price impact: what your trade does to the market

A decentralized exchange doesn't match you with another person. You trade against a pool of two tokens, and the price is set by their ratio. When you buy, you take tokens out of one side and add to the other — which nudges the price against you.

That self-inflicted move is price impact. It isn't a fee, and nobody pockets it. It's simply the cost of being large relative to the pool you're trading in. A $100 swap in a $50 million pool has a price impact so small you'd struggle to measure it. The same $100 swap in a $3,000 pool could move the price several percent.

Price impact is what your trade does to the market. Slippage is what the market does to your trade.

Slippage: everything between quote and execution

Slippage is the wider number. It includes your price impact, and it also includes everything else that touches the pool while your transaction is pending:

Other traders hitting the same pool a block before you.
General volatility — the asset genuinely moving during those seconds.
Bots that deliberately trade around you (see MEV and sandwich attacks).

This is why a quote is an estimate, not a promise. The chain hasn't executed anything yet when you're shown a number.

What "slippage tolerance" actually does

Here's the part most people get backwards. Slippage tolerance is not a dial that gets you a better price. It's a floor — the worst outcome you're willing to accept.

When you set 0.5%, you're instructing the contract: if I would receive more than 0.5% fewer tokens than quoted, cancel the whole thing. The trade reverts, you keep your tokens, and you pay gas for the failed attempt.

So the tradeoff runs in both directions:

Too tight and legitimate trades fail during normal volatility. You burn gas on reverts.
Too loose and you've publicly announced you'll accept a much worse price — which is exactly the opening a sandwich bot needs.

Sensible starting points

These are rules of thumb, not laws — the right number depends on the pair and the moment:

Deep, liquid pairs (ETH/USDC, WBTC/ETH): 0.1%–0.5%.
Mid-cap tokens with reasonable liquidity: 0.5%–1%.
Thin or newly launched tokens: 1%–3%, and expect real cost.
Anything asking for 10%+: stop. That's not a slippage problem, that's a liquidity problem, and it may be a token worth avoiding entirely.

How to actually reduce slippage

Changing the tolerance doesn't reduce slippage — it only changes when you refuse it. To genuinely lose less:

Trade where the liquidity is. Deeper pools mean less price impact for the same size.
Split large orders. Several smaller swaps often beat one big one, though you'll pay gas each time.
Use a router that splits for you. An aggregator can break one trade across several pools at once, so no single pool absorbs the whole order. That's a large part of why aggregators return more tokens than trading on one exchange by hand.
Prefer cheap chains for small trades. On a network where gas is pennies, splitting an order is practical. On expensive chains, gas can outweigh the savings.
Check the price impact figure before confirming — not just the slippage setting. If impact alone is 4%, no tolerance setting saves you.

The quick version

Price impact — caused by your own order size against pool depth. Shown before you confirm.
Slippage — the total quote-to-execution gap, including impact plus everything else.
Slippage tolerance — your cancel threshold, not a price improver.

Read the price impact number, set a tolerance that matches how volatile the pair actually is, and let the router do the work of finding depth. That's most of the skill.

See the real numbers before you sign

Kryllex shows expected output and price impact up front, and routes across 16 chains and 100+ DEXs to find the deepest path — non-custodial, no account.

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Keep reading: The cheapest way to swap crypto · What is MEV?