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L.4 · BEGINNER · 2 MIN

Market Cap: Small, Mid, and Large

Companies are grouped by size based on their market capitalization. Each size category behaves differently in markets.

Quiz · 5 questions ↓

Apple's market cap, live

AAPL — Apple Market Cap, Share Price. Open AAPL on the Ledge to see current values.

Large-cap, mid-cap, and small-cap compared

CategoryMarket CapCharacteristics
Large-capOver $10 billionStable, well-researched, lower volatility (e.g., Apple, Microsoft)
Mid-cap$2B - $10BEstablished but still growing, often acquisition targets
Small-capUnder $2BHigher growth potential but higher risk of failure

Different size cutoffs, and the one we use

Conventions vary. Oxford Ledge uses a 5-tier scheme internally: Mega ≥ $200B, Large $10-200B, Mid $2-10B, Small $300M-$2B, Micro < $300M. MSCI and S&P use slightly different cutoffs. The 3-tier table above is the most common public framing.

Historical returns by company size

Small-caps: higher potential, higher volatility

Small-cap stocks earned higher average returns over the very long 1926-2023 sample, but whether a durable 'small-cap premium' exists is contested: the measured edge concentrates in the smallest stocks and weakens sharply in the decades after it was documented in 1981. (The Size Premium and the Fama-French Alternative module, corpval-17 in the Cost of Capital path, walks through the full controversy.) What is not contested is the volatility: a biotech startup might rise 500% or go to zero. Microsoft is unlikely to do either.

Sort companies by size in the screener

Use the Screener to filter by market cap. Sort descending to see the largest companies, then ascending to see the smallest.

Which size is the likeliest acquisition target?

Which market cap category is most likely to be an acquisition target by a larger company?

Why diversifying across sizes balances risk

Diversifying across market cap sizes helps balance growth potential (small-caps) with stability (large-caps).

Which size fits a low-risk, steady goal?

A retiree wants steady, lower-risk holdings and dislikes large price swings. Based on this module's size categories, which fits the goal best?
Check your understanding

Sit with the ideas.

Which type of company is most likely to double in value over 5 years, but also most likely to go bankrupt?

Why:
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