Go in winter if the goal is a calmer Forbidden City, a Wall with fewer coaches, and hotels that are easier to book than in early October. The low-season palace ticket, published as 40 yuan from 1 November to 31 March, is a small sign of the same fact: the museum itself treats these months as the quiet season. Ticket steps are on Forbidden City tickets.
Wait for another month if anyone in the party is miserable in wind, if you want gardens in leaf, or if your dates land on Chinese New Year. The festival is not “winter, but festive” in a simple way. Offices close, trains fill, and some of the quiet disappears. That decision has its own page: visiting China during Chinese New Year.
For how winter compares with the rest of the year across several cities, use the best time to visit China for culture. This page stays on Beijing.