Official definition · 官方定义
“Market Capitalization (Market Cap) is the most recent market value of a company’s outstanding shares.”[1]
— Corporate Finance Institute, CFI Resource Library · corporatefinanceinstitute.com ↗ · accessed 2026-10-25
Market capitalisation is a company's share price multiplied by its number of shares. It is the market's estimate of what the equity is worth, and it decides which index a stock sits in.
市值等于股价乘以总股本。它是市场对股权的估值，也决定了这只股票会被纳入哪个指数。
Market cap is a size label with consequences. It decides index membership, and index membership decides who is forced to buy. A company crossing into the S&P 500 sees demand from funds that never analyse it. It is also easy to confuse with value: a company can double its market cap while its profits fall, if investors simply pay more for each dollar of earnings.
市值是一个带后果的规模标签：它决定指数归属，而指数归属决定谁被迫买入。一家公司被纳入标普 500，会立刻迎来一批根本不研究它的被动资金。
它也很容易和「价值」混淆：利润下滑的公司，市值照样可以翻倍，只要投资者愿意为每一美元盈利付更多钱。
| Move变动 | Where it appeared出现位置 | What it means这句话在说什么 |
|---|---|---|
| $3tn | The AI trade splits in two 市值 · 第 2 张术语卡 | About $3 trillion of it left S&P 500 companies in one session, which is the number the headlines were quoting. 市值的麻烦在于它不是钱。股价跌 20%，市值少掉的那部分并没有人真的拿走，也不代表公司少了那么多现金；它只是「按今天的报价，全部股份值多少」。所以「蒸发 3 万亿」是估值变化，不是资金流出——真正流出的资金可能只有几百亿。这也是为什么暴跌之后市场能「凭空」长回来。 |
| $108.3bn | Mukesh Ambani's Jio seeks a $108 billion valuation in a record Indian IPO 市值 · 第 5 张术语卡 | At $108.3 billion, Jio would be India's fourth-biggest listed company by market capitalisation, behind Reliance Industries, Bharti Airtel and HDFC Bank. 市值有两个常见误读要避开。第一，市值不等于公司账上有这么多钱，它是全部股票乘当前价格，卖掉一小部分就可能把价格打下来 —— 这正是「自由流通量」重要的原因：流通盘越小，少量资金就越容易推动价格。第二，市值每天都在变，用来横向比较时要看同一时点。本案还有一个特殊之处：Jio 尚未上市，1,083 亿美元这个数字来自发行价区间上限，属于「拟上市市值」，只有挂牌交易之后才变成真实的市值。 |
| $2tn | SpaceX buys the last spectrum it needs to enter US mobile 市值 · 第 7 张术语卡 | SpaceX listed in June and now carries a market capitalisation above $2 trillion — which is why $8 billion is small for it and enormous for the telcos' share prices. 同一个金额对不同公司意义完全不同：对一家市值 2 万亿美元的公司，80 亿美元约占 0.4%；对频谱这项资产本身却是天价。所以读并购新闻时，先算「这笔钱占买方市值的百分之几」，再判断它算不算「大交易」—— 马斯克说它是，那指的是战略意义。 |
| $5tn | Apple's new CEO moves to overhaul the company to run faster and leaner 市值 · 第 7 张术语卡 | Apple's market cap is still close to $5 trillion, and the article asks whether Ternus can “keep growing” it — a $131 billion fall in one day barely moves it. 市值是个「乘积」，所以它对股价的变动有放大效果：苹果总股数约 145.9 亿股，股价每动 1 美元，市值就动约 146 亿美元；跌 1% 就蒸发约 480 亿美元。对比参考：本文里 57 亿美元的专利判赔，只相当于苹果市值的约 0.12% —— 新闻标题里「美国史上最高」的金额，对这家公司的资产负债表来说是一天的正常波动。这就是「大数」和「结构」的区别：判断一件事重不重要，要看它相对什么而言。 |
| $150bn | Nvidia sets biggest-ever buyback plan as AI chip competition weighs on stock performance 市值 · 第 8 张术语卡 | Reuters notes the $150bn increase alone is bigger than the market cap of about 84 per cent of the 500 companies in the S&P 500. 市值排行榜的层级：英伟达是史上第一家市值突破 5 万亿美元的公司（2025 年 10 月），本篇发布时约 5.58 万亿美元。注意市值每天随股价变动；而「企业价值（Enterprise Value, EV）」还要加上净负债 —— 比较两家负债结构不同的公司时，EV 比市值公平。 |
| $200bn | Wall Street expects Meta's AI agent to shape into a new revenue engine 市值 · 第 5 张术语卡 | “Shares have added over $200 billion in market capitalization” — that is the size of the re-rating, not money the company received. 最常见的误读：新闻说「市值一日蒸发 X 亿」，并不代表那 X 亿真的从谁口袋里消失了——它只说明按最新成交价重算，全体股东的账面价值变了这么多。同理，本文的 2000 亿美元是「估值上调」，Meta 一分钱也没收到。 |
Market cap is what the company is worth
It is what the equity is worth at the last trade, not the enterprise value.
Market cap equals cash raised
The company only received money at issuance.
Big market cap means big revenue
It means a high price, which can come from a high multiple on small revenue.
· a $2tn market capitalisation
· market cap
· large-cap
· small-cap
· add to the index
a $2tn market capitalisation 2 万亿美元市值；market cap 市值；large-cap 大盘股；small-cap 小盘股；add to the index 纳入指数。
· market cap vs enterprise value
· shares outstanding vs free float
market cap 只算股权，enterprise value 还要加净债务；shares outstanding 是总股本，free float 是可流通股本。
The company's market capitalisation briefly passed $Xtn, making it the largest in the index.
市值句：公司市值一度突破 X 万亿美元，成为指数最大权重——briefly 这个词说明只是盘中触及。
“About $3 trillion of it left S&P 500 companies in one session, which is the number the headlines were quoting.”
“At $108.3 billion, Jio would be India's fourth-biggest listed company by market capitalisation, behind Relian…”
“SpaceX listed in June and now carries a market capitalisation above $2 trillion — which is why $8 billion is…”
“Apple's market cap is still close to $5 trillion, and the article asks whether Ternus can “keep growing” it —…”
“Reuters notes the $150bn increase alone is bigger than the market cap of about 84 per cent of the 500 compani…”
““Shares have added over $200 billion in market capitalization” — that is the size of the re-rating, not money…”