Slippage: the cost that never appears on the fee schedule
Slippage is the difference between the price you expected and the price you got. It is usually the largest cost in a crypto trade, and almost the only one you can control by changing how you order.
Reviewed by Mason Walker, Ethereum & Layer-2 · Last reviewed September 9, 2026
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Slippage is the gap between the price you saw when you decided to trade and the average price you actually received. It comes from two sources: the market moving between decision and execution, and your order being larger than the liquidity sitting at the best price. On thin pairs it routinely costs more than the exchange's fee, which makes it the most under-managed expense in retail crypto trading.
Why does slippage happen at all?
On an order book, only a limited amount is available at the best price. A larger order consumes that level, then the next, then the next — each worse than the last. Your fill is the average of everything you took. The steeper the book, the worse that average.
On an automated market maker there is no book, but the same logic applies through the pricing formula: the more you take out of a pool, the worse the marginal price becomes. Small trades against a large pool barely register; large trades against a small pool can move the price several percent by themselves.
How does slippage tolerance work on a DEX?
Because a blockchain transaction takes time to confirm, the price you were quoted may no longer exist when your swap executes. The tolerance setting tells the contract how much worse than the quote you will accept — if the outcome falls outside it, the transaction reverts and you keep your tokens, minus the gas you spent.
What is a sandwich attack?
When your pending swap is visible before it confirms, someone can buy the asset just before you, let your trade push the price up, and sell immediately after. Their profit is your slippage. The wider your tolerance, the more room they have to work with.
Defences exist: private transaction relays that keep your swap out of the public queue, aggregators that split orders across pools, and simply trading pairs deep enough that the opportunity is not worth taking. Our guide to what DeFi is sets out the wider mechanics if this is new territory.
How much slippage is normal?
| Situation | What to expect | What to do |
|---|---|---|
| Major pair, small size, calm market | Negligible | Market order is fine |
| Major pair, large size | Noticeable on a single order | Split the order or use limits |
| Small-cap token | Can exceed several percent | Limit orders only; check pool depth first |
| High volatility or a news event | Unpredictable in both directions | Reduce size, widen your time horizon |
How do you actually pay less?
- Use limit orders where you can — they convert slippage risk into execution risk, which is usually the better trade.
- Split a large order into several smaller ones across minutes or hours rather than seconds.
- Check depth before trading, not after; our guide to reading an order book covers how.
- On a DEX, use an aggregator that routes across pools, and keep tolerance as tight as the trade allows.
- Avoid trading into the first minutes of a major announcement, when books are thinnest and spreads widest.
- Compare the executed average price against the quote afterwards — measuring the cost is what makes it manageable.
Slippage is not a malfunction and it cannot be eliminated. It can be measured, budgeted for, and kept small relative to the size of the position, which over a year of trading is worth more than any fee discount.
How do you measure your own slippage?
Slippage stays invisible until you measure it, which is why most people underestimate what trading costs them. The calculation is simple: record the mid price at the moment you sent the order, then compare it with the average price you actually received, and express the difference as a percentage of the trade.
Do this for a month and two things usually become clear. Market orders on thin pairs cost multiples of the exchange's fee, and the cost scales with size in a way that is obvious in hindsight and invisible in the moment. Once you have a number, the fixes — smaller clips, limit orders, better venues — stop being theoretical.
- Most exchanges show the average fill price in the order history; use it rather than your memory of the quote.
- Track fee and slippage separately so you know which one to attack.
- Compare the same trade across two venues before assuming your usual one is best.
- On a DEX, compare the quoted output with the amount that actually arrived in the wallet.
- 1. Automated market makers and constant-product pricing — ethereum.org
- 2. Maximal extractable value (MEV) — ethereum.org
Frequently asked
What is slippage in crypto?
The difference between the price you expected and the average price your trade actually filled at. It grows with order size relative to available liquidity and with market volatility.
What slippage tolerance should I set on a DEX?
As tight as the trade allows — often a fraction of a percent on deep pools. If a swap only succeeds with a wide tolerance, the pool is too thin for your size rather than the setting being wrong.
Why did my swap fail and still cost gas?
The transaction executed, found the outcome outside your tolerance, and reverted. The network still did the work of processing it, so the gas is spent even though no swap occurred.
Do limit orders eliminate slippage?
They eliminate negative slippage by refusing prices worse than your limit. In exchange, the order may fill partially or not at all.
Is slippage worse on decentralised exchanges?
Not inherently. It depends on pool depth versus book depth for the pair in question, plus the delay between quote and confirmation, which is unique to on-chain execution.
Kayla Peterson is a DeFi Research Analyst at Crypto Almanac Daily, where she specializes in decentralized finance, lending protocols, decentralized exchanges (DEXs), liquidity markets, yield strategies, and tokenomics. Her work focuses on analyzing the mechanics behind DeFi ecosystems, helping readers understand how lending platforms, automated market makers, liquidity incentives, and governance models influence the broader digital asset economy. Kayla regularly covers major protocols, emerging trends in on-chain finance, and the evolution of decentralized financial infrastructure through data-driven research and in-depth market analysis. Before joining Crypto Almanac Daily, she researched blockchain-based financial systems and digital asset markets, building expertise in protocol design, token economics, and decentralized capital markets. Her reporting combines technical accuracy with clear explanations, making complex DeFi concepts accessible to both experienced investors and newcomers to the industry. At Crypto Almanac Daily, Kayla contributes daily market coverage, protocol analyses, educational guides, and long-form research articles. Her goal is to provide readers with reliable, objective insights into the rapidly changing world of decentralized finance while highlighting the opportunities and risks shaping the next generation of financial innovation.
This guide is educational and general in nature. It is not financial, investment, legal or tax advice, and it does not account for your circumstances. Crypto assets are volatile and you can lose the money you put in. See our editorial policy and methodology.
