> ## Documentation Index > Fetch the complete documentation index at: https://docs.soroswap.finance/llms.txt > Use this file to discover all available pages before exploring further. # Swap > Swapping Stellar assets through Soroswap AMMs or the Aggregator, and the constant product formula behind pricing. A **swap** is the process of exchanging one Stellar asset for another using liquidity from Soroban-based [**Automated Market Makers (AMMs**](/concepts/amm)**)**. Swaps can be executed directly through the [**Soroswap AMM** ](/amm)or routed via the [**Aggregator**,](/concepts/aggregator) which optimally resolves the operation by finding the **best available price at the time** through an **intelligent distribution** across supported AMMs.\ \ 👉🏽 [How to Swap](/getting-started/how-to-swap)\ Follow the [Swap Tutorial](/tutorials/doing-swap) ### How does a swap work? **User selects two assets** – one to sell and one to receive. 1. **Input amount is defined** – the app estimates the output based on current pool conditions. 2. **Router SDK scans available pools** – if the Aggregator is enabled, it calculates the best distribution **`DexDistribution`**. 3. **User confirms the swap** – the smart contract receives the input asset and performs the swap. 4. **User receives the new asset** – if it's the first time, a **trustline** must be signed to accept the asset. ### 📐 Constant Product Formula Each AMM in Soroswap follows this formula: ``` x * y = k ``` Where: * `x` = balance of asset A * `y` = balance of asset B * `k` = constant product (remains unchanged) When someone swaps A for B: * A is deposited into the pool * B is withdrawn * The price updates to maintain the balance This model ensures continuous liquidity. 🔜 **Next:** [Fees](/concepts/fees)\ 🔙 **Previous:** [Liquidity Pools](/concepts/liquidity-pools)