From trading methods to DeFi infrastructure: How Automated Market Makers (AMM) are transforming cryptocurrency trading

Why Do Decentralized Exchanges Need AMM?

Traditional financial markets operate simply: buyers and sellers quote prices, and a trade is executed once both parties agree on a price point. This logic is used for stocks, gold, real estate, and more. But in the decentralized blockchain world, this model faces a major problem—insufficient liquidity.

Early DEXs (Decentralized Exchanges) adopted an order book model, but found that not enough traders were willing to participate continuously, making it difficult to complete trades quickly. This bottleneck hindered the development of the entire DeFi ecosystem.

Automated Market Makers (AMM) are an innovative solution to this problem. They change the understanding of trading—no longer needing to wait for matching buy and sell orders, but instead enabling trades at any time through smart contracts and liquidity pools.

Liquidity Pools: The Core Engine of AMM

The core of AMM operation is the liquidity pool. Simply put, it’s a token jar—users deposit cryptocurrencies into it, and the prices of these tokens are determined by a fixed mathematical formula, not by human manipulation.

Any user with internet access and ERC-20 tokens can become a liquidity provider. They deposit tokens into the pool, and each time someone trades through that pool, the provider earns a fee (usually 0.3%). If enough participants join, the pool grows larger, increasing liquidity and making trades smoother.

This incentive mechanism breaks the deadlock faced by traditional DEXs. Moreover, liquidity providers can now earn additional rewards through “liquidity mining,” earning project tokens, which further boosts participation.

Constant Product Formula: The Mathematical Magic of AMM

AMM’s ability to automatically price assets relies on an elegant mathematical formula: x × y = k

Where x and y represent the quantities of two assets in the pool, and k is a constant. This formula was initially proposed by Ethereum founder Vitalik Buterin and later popularized and applied in practice by Uniswap.

How does it work? Suppose there’s an ETH-BTC liquidity pool. When someone buys ETH, the ETH in the pool decreases, causing the ETH price to rise; simultaneously, BTC in the pool increases, causing BTC’s price to fall. Regardless of how prices fluctuate, the system ensures the prices stay on the curve defined by the formula, reflecting a relatively accurate market price.

This automatic balancing mechanism also has another advantage: when the AMM’s price deviates too far from other exchanges, arbitrage traders will automatically step in, exploiting the price difference until the market rebalances.

AMM in Practice: Three Leading Projects, Each with Its Strengths

Since Vitalik introduced the concept of AMM, the DeFi ecosystem has rapidly evolved. Today, three major AMM projects dominate, each with unique features:

Uniswap adopts the simplest design—users can create liquidity pools for any pair of ERC-20 tokens with a 50%/50% ratio. Thanks to its simplicity and flexibility, Uniswap has become the highest-volume decentralized exchange on Ethereum, with its token UNI even entering the top ten by market cap.

Curve is optimized for stablecoins, establishing specialized pools for trading assets of similar value. This allows Curve to offer the lowest slippage and most efficient trading experience in stablecoin transactions.

Balancer further expands AMM flexibility, allowing users to create pools with up to 8 different assets in any ratio, breaking the 50%/50% limit of Uniswap.

The Sign of Decentralized Finance

From order book models to AMMs, the emergence of AMM marks the maturity of the DeFi ecosystem. It not only solves the liquidity issues faced by early DEXs but also embodies the blockchain ideal of “no centralized control, anyone can participate in innovation.”

Liquidity pools based on AMM have become essential infrastructure within DeFi. Many emerging DeFi projects are adopting the AMM model, creating a virtuous cycle. This evolution shows that AMM has grown from an experimental idea into a core tool driving the entire industry forward.