Glossary
Bid-Ask Spread
The gap between the highest buy offer (bid) and the lowest sell offer (ask) on a market — a primary measure of execution cost and market quality.
On an order book, the bid is the highest price someone is willing to pay; the ask is the lowest price someone is willing to sell. The difference is the spread, and a trader crossing the spread (taking immediate execution) pays half of it in expected cost.
Tighter spreads signal a more efficient market: more makers competing, lower friction. Widening spreads signal stress — makers pulling quotes, volatility spiking. Crypto spreads on the top USD pairs are now competitive with traditional venues; long- tail tokens still trade with significantly wider spreads.