The term closing range refers to the high and low price at which trades occurred at the close of the exchange. The closing range would include both bid and offer prices.
The high and low price at which a security trades just before a market closes is referred to as its closing range. The same holds true for the futures market, where the minimum and maximum prices at which a contract trades constitute its range. This would typically include the bid, or price at which a trader would buy a security. It would also include the offer, or price at which a trader would sell a security.
Given the above, the closing range, or spread, for a security would be relatively narrow. The hours during which an exchange is open will vary by geographic region. The New York Stock Exchange as well as the NASDAQ are open from 9:30 a.m. Eastern Time and close at 4:00 p.m. Eastern Time.