Why did my swap go through but I received far less than expected

05 September 2026

You received far less because the swap executed at a worse price than the quote you saw, most often due to a combination of low liquidity and high slippage. The transaction confirmed on-chain, but the actual exchange rate degraded significantly between when you clicked "swap" and when the trade settled.

The core problem is how automated market makers (AMMs) price trades. Every swap moves the pool's ratio. In a shallow pool - typical for low-liquidity tokens and memecoins - even a small trade can shift the price substantially. The quote you saw was a snapshot. By the time your transaction was mined, other traders may have moved the pool, or the frontend simply estimated a price that assumed more depth than existed.

Consider a concrete example. A memecoin pool holds 1,000 tokens and 1 ETH. The quoted price is 1 token = 0.001 ETH. You swap 100 tokens. That removes 10% of the token supply from the pool, drastically changing the ratio. You do not get 0.1 ETH. You get something closer to 0.09 ETH, because each successive token in your order trades at a worse rate. This is price impact. It is not a bug. It is how constant product formulas work.

Several specific factors cause the gap between quote and received amount:

Slippage tolerance. Your wallet or the swap interface set a maximum slippage percentage - often 0.5% or 1% by default. If the true execution price falls within that tolerance, the swap goes through. But that tolerance does not guarantee you get the quoted rate. It only guarantees the transaction does not revert if the rate moves within that band. A 1% slippage tolerance can hide a 15% price impact if the frontend calculated the quote with a different, more optimistic price.

Frontrunning and sandwich attacks. In public mempool environments, bots watch pending transactions. They see you are about to buy. They buy first, driving the price up, then sell after your trade completes. You receive fewer tokens than the market rate at the moment you submitted. Your transaction still succeeds. The bots profit from your slippage.

Stale quotes and latency. The frontend fetches a price from a node, but by the time your signed transaction reaches the chain, the pool state has changed. A popular memecoin can see dozens of trades per block. The quote is old before you hit confirm.

Fee-on-transfer tokens. Some tokens deduct a percentage on every transfer. The swap contract sends 100 tokens, but the receiving contract gets 95. The AMM calculates the swap based on the full 100. You get the output for 100, but you only supplied 95. The effective rate is worse. This is invisible in the quote unless the frontend specifically checks the contract's transfer fee.

Multi-hop routes. If your token only trades against a dead coin, as the sibling page covers, the swap may route through several pools. Each hop adds its own price impact and fees. The total can be far higher than a direct pair.

What should you do? Always check the pool's total value locked (TVL) before swapping. The page "How can I tell if a token has enough depth for my swap size" explains how to estimate this. Set your slippage tolerance manually to a realistic number - 0.5% is often too tight for illiquid pairs, but 5-10% invites heavy losses. Use the simulate transaction feature if your wallet supports it. That shows the actual output before you sign, not a frontend estimate.

If you consistently receive far less than expected, the honest answer is that the token is not liquid enough for your trade size. The hub page "Swapping in and out of memecoins" covers the broader strategy: know your exit before you enter, and never assume a quote is the price you will get. The mechanics are unforgiving. The math does not care about your expectations.

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