Spread
In short
The spread is the gap between the best buy and best sell price. It is a hidden trading cost: you buy at the top, sell at the bottom.
Liquid pairs like BTC/USD have paper-thin spreads; exotic coins can have painful ones. Frequent traders often lose more to spread than to official fees.
Why am I instantly "down" after buying?
You are seeing the spread: selling would only fetch the lower bid price.
Related terms
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