What is an order book? How crypto trades get matched
By SendPay Business · · 2 min read
An order book is the live list of buy and sell orders on an exchange. Buyers post bids, sellers post asks, and a trade happens when a bid and an ask meet at the same price.
Bids, asks and the spread
The highest bid and the lowest ask sit closest together. The gap between them is the spread; a narrow spread usually means the market is busy and easy to trade.
Market vs limit orders
- Market order: buy or sell straight away at the best price available.
- Limit order: set the price you want and wait for the market to reach it.
Slippage and liquidity
A large market order can use up several price levels in the book, so the average price ends up worse than expected. That's slippage, and it's bigger when there are few orders, which is called low liquidity.
Where SendPay fits
SendPay crypto exchange platforms let your customers buy, sell and hold crypto under your own brand, with assets held with regulated partners, and you set your own trading fee.
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Create your own financial platform.
Pick a template, name it, brand it, preview every page before you pay. Your brand, your users, your fees.
Build my platform →Questions people ask
What price would a market order get?
See how an order fills level by level and what slippage it causes.
Order book calculator →What did slippage cost me?
Compare the price you expected with the price you got.
Slippage calculator →Read next
This guide is general information, not legal or financial advice. SendPay Business is a technology company, not a bank, and does not take deposits; regulated services on the platforms are provided by licensed partners. PayPal, Patreon and Substack are named as reference points only and are not affiliated with SendPay Business.