What is an automated market maker in crypto?
An automated market maker is a smart contract that trades crypto from liquidity pools. Prices follow a formula based on pool balances, with no order book.
Vahe HakobyanEditor-in-chief
Updated Oct 6, 20263 min readFact-checked
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- Liquidity providers earn a share of the swap fees.
- Traders face slippage and smart-contract risk.
- A centralized exchange matches orders; an AMM does not.
Traditional finance relies on market makers for trading. The crypto version runs on code instead of a company. You connect a wallet, and the pool does the rest.
How does an AMM work?
An AMM holds tokens in a pool instead of an order book. You trade against the pool, so no buyer and seller are matched. The pool's balances set the price through a formula.
- Many AMMs use a constant product formula between the two tokens.
- The price of a token rises as the pool holds less of it.
- A large swap shifts the balances more and moves the price further.
How do people use AMMs?
You can generally swap from a compatible wallet, though some front ends or pools may restrict access or require checks. No company account is needed. Liquidity providers add tokens to a pool and receive a share of the fees.
What risks and limits do AMMs have?
Liquidity providers face impermanent loss, which can be larger than the fees they earn. Traders face slippage, and a bug or exploit in the contract can drain a pool. Automated does not mean safe.
How is an AMM different from an exchange?
A centralized exchange runs an order book. Buyers post bids and sellers post asks, and the company matches them. An AMM has no order book and no company matching trades. The pool's formula sets the price.
Frequently asked questions
It is the gap between the pool value of your tokens and what they would be worth if you had held them. The loss becomes real when you withdraw.
The IRS treats crypto as property, so swapping one token for another usually creates a taxable event. Providing liquidity can also have tax consequences.
Yes. A token in the pool can fall to zero, and an exploited contract can take the pool's coins.
There is no AMM-specific US rulebook. US agencies may apply existing securities, commodities, and money-transmission rules to certain AMM operators, developers, or front ends, depending on the facts.
