Why two swap sites show different final amounts for the same pair

05 September 2026

Two swap sites show different final amounts for the same pair because each site applies its own combination of spread, liquidity source, and fee structure. No two sites pull from the same pool in the same way, so the amount you receive will vary.

The core reason is that most swap sites do not directly match buyers and sellers. Instead, they route your trade through a series of liquidity pools - often from different decentralized exchanges or aggregators. Each site has its own algorithm for choosing which pools to use, and those algorithms prioritize different things: some chase the best raw price, others minimize network fees, and others prioritize speed. The same trade routed through different paths will yield different amounts.

For example, one site might split your trade across three pools to get a better average price, while another sends the entire trade to a single pool. Splitting can reduce slippage on large trades, but it may also incur extra network fees for each leg of the route. Another site might use a pool that charges a higher fee per trade but offers deeper liquidity, which can matter for large amounts. These choices are invisible to you, but they directly change the final number.

Also, each site sets its own spread. The spread is the difference between the market price and the price you actually get. Some sites advertise a "zero-fee" swap but build a wider spread into the exchange rate. Others charge a visible fee but offer a tighter spread. The quoted amount you see on the screen already includes that site's spread. Comparing two sites therefore means comparing two different spreads, routed through different pools, with different network fee estimates.

Network fees add another layer of variance. The fee to send a transaction on Ethereum, for instance, fluctuates with network congestion. A swap site estimates this fee when it shows you a quote. But the estimate depends on the site's assumptions about gas price and the complexity of the route. One site might assume a faster, more expensive transaction; another might assume a slower, cheaper one. That difference shows up in the final amount.

Finally, the quoted amount is not guaranteed. As covered on the sibling page "How a floating rate swap can change between the quote screen and the confirmation," the price can shift between the moment you see the quote and the moment the transaction is mined. This is especially true on volatile markets or congested networks. Two sites quoting at the same time can still land on different final amounts because their quotes are snapshots taken at slightly different instants.

To summarize: different liquidity sources, different routing algorithms, different spreads, different fee estimates, and different timing all cause the same swap pair to yield different amounts on different sites. The only way to know what you will actually receive is to compare the final, confirmed transaction - not the initial quote. For a deeper breakdown of where each cost comes from, see the hub page "What a crypto swap actually costs."

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