Here’s a trap beginners fall into: thinking a $500 stock is “bigger” or “more expensive” than a $10 one. On its own, the share price tells you almost nothing.
Why price alone is meaningless
A company’s value is split across its shares. Split the same company into more shares and each one costs less — without the company being any smaller. A $500 stock with 1 million shares is worth less in total than a $10 stock with 1 billion shares. To compare companies, you need price and the number of shares.
Market capitalisation
Market cap combines them into the figure that actually measures size:
Market cap = share price × shares outstanding
It’s what the market thinks the whole company is worth. A $10 stock with 5 billion shares has a $50 billion market cap; a $500 stock with 10 million shares is worth $5 billion — twenty times smaller, despite the bigger sticker price.
Size bands
Investors group companies by market cap:
- Large cap — roughly $10 billion and up. Established, household names; generally steadier.
- Mid cap — roughly $2–10 billion. Often still growing.
- Small cap — under ~$2 billion. More room to grow, but more volatile and riskier.
(The exact cut-offs vary; treat them as rough bands.)
Why it matters
Size is a rough guide to risk and stability. Large caps tend to move less violently and survive downturns; small caps can grow faster but fall harder. Knowing a company’s market cap tells you far more about what you’re buying than its share price ever could.
The takeaway
Market cap = price × shares outstanding — the total value of the company, and the right way to compare sizes. Share price by itself is just the value of one slice, and says nothing about how big the pie is.