共计 is an adverb meaning 'in total' or 'altogether', used to introduce a sum or aggregate figure. It combines 共 (gòng), meaning 'together' or 'jointly', and 计 (jì), meaning 'to calculate' or 'to count'. Together, they literally mean 'to jointly calculate', emphasizing the final result of adding up multiple items, amounts, or occurrences. It is commonly found in formal writing, reports, financial summaries, academic texts, and spoken explanations where precision and clarity about totals are important.

The word typically appears at the beginning or middle of a sentence before a numeral or noun phrase indicating quantity—e.g., '共计127人' (127 people in total). Unlike colloquial alternatives like 一共, 共计 carries a slightly more formal, objective, and statistical tone, often implying careful enumeration rather than casual estimation. It does not function as a verb or noun on its own and must always modify a quantified expression.