A crypto exchange is an online marketplace where you buy, sell and trade cryptocurrencies. It matches your order with someone else's order through an order book, publishes the price for each trading pair, and charges a fee for arranging the trade.

The top guides describe the steps but none of them follows one trade from dollars to coins and back with the fees included. One guide lists fee ranges of 0.5% to 1.5% without applying them. Another gives a six-step process but no numbers. A third explains the order book in detail but never shows a buy and a sell in the same example. This guide runs one $1,000 trade end to end.

There are two main kinds of exchange. A centralized exchange is run by a company: you create an account, complete identity checks, and your funds sit in wallets the platform controls while you trade. A decentralized exchange runs on smart contracts on a blockchain: you trade directly from your own wallet, with no company holding your funds, and it usually offers crypto-to-crypto swaps only. Aggregators sit on top and compare rates across many services.

The heart of most exchanges is the order book. It is a live list of buy orders, called bids, and sell orders, called asks. Suppose the best bid for Bitcoin is $99,990 and the best ask is $100,010. The gap between them, $20, is the spread. Place a market buy and you pay the lowest ask, $100,010. Place a limit buy at $99,990 and you wait for a seller to meet your price. Matches are ranked by price first, then by time: the earliest order at the best price is filled first.

Worked example: you deposit $1,000 and buy Bitcoin at $100,000 per coin. The exchange charges a 0.5% fee, which is $5. You receive $995 worth of Bitcoin, which is 0.00995 BTC. Later Bitcoin rises to $110,000. Your 0.00995 BTC is now worth $1,094.50. You sell and pay another 0.5% fee of $5.47. You receive $1,089.03. Your profit is $89.03 on $1,000, which is 8.9%, even though Bitcoin rose 10%. The two fees took $10.47, which is about 1.05% of your starting money.

Trading fees are not the only cost. Exchanges may also charge deposit fees, withdrawal fees, and the spread itself, which is the gap between the buy and sell price. On a centralized exchange your money and crypto sit in the exchange's own accounts while you use it, so withdrawing to your own wallet matters for long-term holding. No exchange can guarantee trading profits, and prices can move fast in either direction.

Starting on a centralized exchange follows six steps. Create an account and complete any identity verification. Deposit funds by bank transfer, card or crypto. Select a trading pair, such as BTC/USDT. Choose a market order to buy at the current price or a limit order to buy at a price you set. Confirm the trade and check the fee before you submit. Then withdraw your crypto to your own wallet, or hold it on the exchange if you plan to trade again soon.

Q: What is a crypto exchange in simple terms?

A: It is an online marketplace that matches people who want to buy crypto with people who want to sell it, and charges a fee for arranging the trade.

Q: What is the difference between a centralized and a decentralized exchange?

A: A centralized exchange is run by a company that holds your funds and requires identity checks. A decentralized exchange runs on smart contracts and lets you trade from your own wallet.

Q: How does an exchange decide the price of Bitcoin?

A: The exchange does not set the price. The price is the last price at which a trade happened on that exchange, set by the buyers and sellers in its order book.

Q: How much does it cost to trade on a crypto exchange?

A: Trading fees often range from 0.5% to 1.5% per trade, plus possible deposit, withdrawal and spread costs. A $1,000 buy and sell at 0.5% each costs $10.47 in total.