Two separate things cause slippage, and telling them apart matters because they call for different responses. One is the market moving on its own. The other is your own order being large enough to move it. The starting point for both is covered in what is slippage in crypto; this article goes into each cause properly.
Cause one: the price genuinely moved
A quote describes conditions at an instant. Your order arrives some measurable time later — after you read the screen, after you confirm, and, on-chain, after the transaction propagates and waits to be included in a block. During that window other people are trading, and the price moves for reasons entirely unrelated to you.
This kind of slippage scales with how volatile the asset is and how long the gap between quote and fill lasts, not with how much you are trading. A small order and a large order placed at the same moment into the same fast-moving market both experience it. It is also symmetrical: the price is as likely to move in your favour as against you, which is why positive slippage exists at all.
Cause two: not enough depth at the quoted price
The second cause is structural rather than temporal, and it is the one your own trade creates. Any market has only a finite amount available at any given price. A quote reflects the best price, which applies to the first portion of your order. Once that portion is consumed, the next portion fills at the next-best price, and so on.
The result is that your effective price is an average across every level your order consumed, and that average is worse than the headline quote. Crucially, this is deterministic rather than random: given the same depth and the same order size, you get the same result every time. It does not depend on luck or timing, and unlike volatility slippage, it is never symmetrical — consuming depth always moves the price against you, never in your favour. The worked examples page shows this with concrete arithmetic.
Why the two causes look identical on your screen
From the user’s side, both produce the same message: you expected one amount and received another. Distinguishing them takes one question — would a much smaller order have had the same problem?
If a tiny test trade fills cleanly and a large one does not, the cause is depth, and the response is to reduce order size, split the order, or trade a deeper market. If even a small trade slips noticeably, the cause is volatility, and the response is different: a limit order, or simply waiting, rather than resizing. Most interfaces show an estimated price impact figure before you confirm, which is specifically an estimate of the depth-driven component — it does not attempt to predict how the market will move.
Which assets are most affected
Depth-driven slippage is worst on thinly traded assets, which in practice means newly launched tokens and small pairs. Volatility-driven slippage is worst during fast-moving conditions, which can affect even the largest and most liquid assets. The two frequently compound: sharp moves tend to arrive alongside thinner-than-usual depth, so the worst fills tend to happen in exactly the conditions where people most want to trade quickly. That combination is also what makes a wide slippage tolerance setting most costly.
Frequently asked questions
Does a bigger order always mean more slippage?
For the liquidity-driven component, yes u2014 a larger order consumes more depth and fills progressively worse. The volatility-driven component does not scale with order size at all.
What is price impact, and is it the same as slippage?
Price impact is the portion of slippage caused by your own order consuming available depth. It is an estimate shown before you trade, and it excludes any movement the wider market makes.
Can I tell which cause affected my trade?
Usually yes. If a much smaller trade fills cleanly while a large one does not, the cause is depth. If even small trades slip noticeably, the market itself is moving.