Market Cap Calculator
Calculate market capitalisation, classify a stock by tier, or compute fully diluted market cap including dilutive securities. Works with any currency.
Try another scenario
How to Use This Calculator
Tab "Calculate"
Enter the current share price and shares outstanding (total issued shares minus treasury stock). The calculator instantly computes market capitalisation and formats it as a readable figure ($2.91T, $600M, etc.). Find shares outstanding in the company's latest 10-K, 10-Q, or on financial data sites.
Tab "Tier Classification"
Enter the same share price and shares outstanding. The calculator computes market cap and classifies the company into one of six tiers: Nano (<$50M), Micro ($50M–$300M), Small ($300M–$2B), Mid ($2B–$10B), Large ($10B–$200B), or Mega (>$200B). Each tier includes what it means for liquidity, volatility, and analyst coverage.
Tab "Fully Diluted"
Enter the share price, basic shares outstanding, and all dilutive securities: stock options, RSUs, convertible bonds (converted to equivalent shares), and warrants. The calculator shows the fully diluted market cap and overhang percentage — how much potential dilution exists.
The Formulas
Market Cap = Share Price × Shares Outstanding
Fully diluted market cap:
Fully Diluted MC = Share Price × (Basic Shares + Stock Options + RSUs + Convertible Bonds + Warrants)
Overhang percentage:
Overhang % = Total Dilutive Securities / (Basic Shares + Total Dilutive Securities) × 100
Tier classification thresholds:
Nano < $50M < Micro < $300M < Small < $2B < Mid < $10B < Large < $200B < Mega
All calculations are universal. Market cap reflects equity value only — for total business value including debt, use the Enterprise Value Calculator.
Worked Examples
Example 1 — Mega cap: Apple-sized company
A technology giant trades at $192.53 per share with 15.115 billion shares outstanding.
At $2.91 trillion, this company falls in the mega-cap tier — very high liquidity, low volatility, and extensive analyst coverage. Virtually every institutional investor holds this stock.
Example 2 — Small cap: growth-stage company
A biotech company trades at $12.45 per share with 85 million shares outstanding.
At $1.06 billion, this company is a small cap. Lower analyst coverage and liquidity mean wider bid-ask spreads, but the growth potential can be significant.
Example 3 — Fully diluted: tech company with equity compensation
A mid-cap tech company at $45.00 per share with 500 million basic shares plus 60 million dilutive securities.
The 10.71% overhang is at the boundary of moderate and high dilution. Investors should monitor how quickly these securities vest and whether the company is repurchasing shares to offset dilution.
Understanding Market Capitalisation
What Is Market Cap?
Market capitalisation is the total market value of a company's outstanding shares of stock. It is the simplest measure of company size and is calculated by multiplying the current share price by the total number of shares outstanding. Market cap changes in real-time as the share price moves.
Market Cap Tiers Explained
Companies are grouped into tiers based on their market cap. Each tier has distinct investment characteristics:
Mega cap (>$200B): Household names with dominant market positions. The most liquid and least volatile stocks. These form the backbone of index funds and pension portfolios.
Large cap ($10B–$200B): Established businesses with proven track records. Good balance of growth and stability, with strong analyst coverage and institutional ownership.
Mid cap ($2B–$10B): The growth sweet spot. Large enough to be stable, small enough to have significant upside. Often acquisition targets for larger companies.
Small cap ($300M–$2B): Higher growth potential with more risk. Less analyst coverage creates information asymmetry that diligent investors can exploit.
Micro and nano cap (<$300M): The most speculative tier. Very low liquidity, wide spreads, and minimal analyst coverage. Suitable for experienced investors with strict position sizing.
Basic vs Fully Diluted Market Cap
Basic market cap uses only currently outstanding shares. Fully diluted market cap includes all shares that could exist if every option were exercised, every RSU vested, every convertible bond converted, and every warrant exercised. The gap between the two reveals potential dilution risk.
Market Cap vs Enterprise Value
Market cap measures equity value only. Enterprise value (EV) = market cap + total debt + preferred stock + minority interest − cash. EV is more useful for comparing companies with different capital structures. A company with a $10B market cap and $5B in net debt has an enterprise value of $15B.