AMM price impact calculator

How the calculation works

Effective input = input × (1 - fee). Output = output reserve × effective input ÷ (input reserve + effective input). Average rate = output ÷ total input.

Worked example

Example: a fee-free pool with 1,000 tokens on each side returns about 90.909091 output tokens for 100 input tokens. Average execution is 9.090909% below the starting rate.

How to use the result

Enter reserves in token quantities. The two tokens may have different units; keep input and output amounts on the correct side.

Execution shortfall includes the fee. Curve impact excludes it. Slippage refers to changes while a transaction waits and is separate from the trade's own price impact.

What this result leaves out

• One full-range constant-product pool only. This is not a live router quote or a model of concentrated liquidity.
• No gas, transfer-tax tokens, MEV, multi-hop routing or reserve changes while pending.

Method and sources

• Uniswap: swaps, price impact and slippage
• Uniswap v2 whitepaper

Calculation method reviewed 23 October 2026. This is an estimate from your inputs, not investment or tax advice.