Enter the pool reserves and your trade size to see the exact fill a constant-product AMM will give you — before you send the transaction, not after.
A constant-product pool holds reserves x and y such that x · y = k stays constant through every swap. Spending Δy (after fee) returns:
Δx = (x · Δy) ÷ (y + Δy)
Your average fill is Δy ÷ Δx, and the impact is how far that sits above the spot price you saw before trading. The fee is taken from the input, so it is charged whether or not the swap is a good idea.
Spend 1% of a pool's quote reserve and impact is roughly 1%. Spend 10% and it is roughly 10%, not 1% — and the curve steepens from there, because each unit you buy makes the next unit more expensive. This is the single arithmetic fact that separates a strategy that works at $500 from the same strategy at $50,000.
Impact is what the pool charges you deterministically. Slippage tolerance is the extra room you grant for the pool to move between submission and settlement — and that room is exactly the budget a sandwich bot has to work with. Compute the impact here first; then set tolerance a little above it, not at a comfortable round number.
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No. Price impact is the cost your own order causes and can be computed in advance. Slippage is the difference between the price you expected and the price you got, which includes other people's trades landing before yours.
The principle holds but the numbers differ: within an active range a concentrated position behaves like a much larger constant-product pool, so impact is lower until price leaves the range.
Any block explorer or DEX analytics page shows the current reserves of a pair. The DexLadder Pool Radar reads them live.
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