Volume
Volume is how much of a trading instrument changed hands in a period: the number of shares, contracts or units traded, usually drawn as bars under the candles.
Every trade has a buyer and a seller, so volume counts each trade once. High volume means many orders met at those prices; low volume means few did. On 2 October 2026 the Bitcoin perpetual on Binance traded about 232,000 BTC, against a median of about 143,000 BTC a day from 10 September to 14 October, so that day’s long upper wick was built by heavy trading.
Learn more: what does a long wick mean?.