Bid
A bid is an offer to buy an asset at a specific price. All open bids together form the buy side of an order book, and the highest one is called the best bid.
What a bid is
When someone places a buy limit order, for example to buy 2 coins at 50 USDC each, that order becomes a bid. It waits in the order book until a seller accepts it or the buyer cancels it. Bids are listed from the highest price down, because the highest bid is the most attractive one for a seller.
Why the best bid matters
The best bid is the highest price anyone is currently willing to pay. If you sell with a market order, you sell into the bids, starting with the best one. That is why traders say a market sell order hits the bid.
The best bid and the best ask together define the bid-ask spread. The price shown as the current price on many platforms is the last traded price, which usually sits between or at these two levels.
An example
Say the bid side shows 99.8 for 4 coins, 99.5 for 6 coins and 99.0 for 20 coins. If you sell 8 coins at market, you get 99.8 for the first 4 and 99.5 for the next 4. Your average is 99.65, a little below the best bid, because your order was larger than the volume at the top level.
Things to keep in mind
Bids are not commitments forever. They can vanish within milliseconds, especially in fast markets, so the volume you see may not be there when your order arrives. In thin markets the gap between bid levels can be large, so a sizeable sell order can push the price down noticeably.
Ask Coach about it
Coach is the AI on AtenaCrypto. It explains crypto with live market data, in plain words.
What does the size of the bid side tell me about a market, and what does it not tell me?Ask Coach →
Frequently asked questions
What is the difference between bid and ask?
A bid is an offer to buy; an ask is an offer to sell. The best bid is always below the best ask, and the gap between them is the spread.
What does it mean to hit the bid?
It means selling immediately at the best available buy price, usually with a market order, instead of waiting for a higher price with a limit order.
Is the bid price the price I pay?
No. If you buy right away, you pay the ask. The bid is the price you receive if you sell right away.
Related terms
Learn it step by step
AC Learning explains these ideas in interactive lessons — the first eight sections are free.
Open AC Learning → Create a free accountAll glossary terms · Educational reference only — not investment, legal, tax or financial advice.