What is crypto market cap, and what does it leave out?
Market cap is the first number most crypto lists show, and the one most often misread. It is a simple multiplication, and knowing what goes into it tells you what it can and cannot say.
Education only, not investment, tax or legal advice. Crypto-assets are high-risk — risk disclosure.
The short answer
Crypto market cap is the latest price of one coin multiplied by the number of coins in circulation. It is a quick way to compare the size of different assets, but it is not money invested, and it ignores coins that are locked up or not yet created.
Key takeaways
- Market cap multiplies one coin's latest price by the circulating supply, the crypto version of shares outstanding.
- Circulating, total and maximum supply are different numbers; using the wrong one changes the answer.
- Fully diluted valuation (FDV) multiplies the price by the maximum supply, showing what the asset would be worth at today's price if every coin existed.
- Because market cap values every coin at the last trade, it can jump on thin trading and does not measure money put in.
How is crypto market cap calculated?
The idea comes from the stock market. The SEC defines a company's market capitalisation as the market value of its shares, generally calculated by multiplying the number of shares outstanding by the market price of one share1. Investor.gov gives the same formula: current public price per share times total outstanding shares2.
Crypto data sites apply the same multiplication to tokens. The usual input is the circulating supply: the coins that exist and can actually be traded. A 2019 European Central Bank paper on crypto-assets used this circulating-supply definition and noted that it corresponds to the "free float" of each asset3, the share-market term for stock that is freely tradable rather than held by insiders.
Worked example
A simple market cap sum
Token ABC last traded at 2.00 dollars and has 100 million coins in circulation.
Market cap = 2.00 × 100,000,000 = 200 million dollars.
Illustrative numbers. Calculated in code.
Because the formula is the same for every asset, market cap lets you compare the relative size of two coins with very different prices. A coin priced at a few cents can have a larger market cap than one priced in the thousands if it has vastly more units in circulation.
What is the difference between circulating, total and maximum supply?
Token supply comes in three layers, and they map neatly onto terms the SEC uses for company shares. Outstanding shares are those issued and still held by shareholders; authorised shares are the most a company is permitted to issue under its founding documents; and the public float is the part held by ordinary outside investors rather than insiders1.
Three supply numbers and their stock-market cousins
Bitcoin is the clearest example of a maximum supply written into code. New bitcoin is created in the first transaction of each block as a reward to whoever creates the block7. The Bitcoin Core software starts that reward at 50 BTC and halves it every 210,000 blocks, which the code comments estimate at roughly four years5. Our explainer on the bitcoin halving covers the schedule in detail.
Figure · New bitcoin per block in the first four reward eras
Adding up every era gives a ceiling of about 20,999,999.98 BTC, just under the familiar 21 million (our calculation in code from the halving rule5). The software also contains a 21 million BTC limit, but a comment beside it says this is a sanity check rather than the actual money supply, which is lower4.
What is fully diluted valuation (FDV)?
Fully diluted valuation, usually shortened to FDV, swaps circulating supply for maximum supply: FDV = price × maximum supply. It answers a hypothetical question: what would the whole asset be worth at today's price if every coin that can ever exist were already out?
The name borrows from company finance. The SEC describes dilution as what happens when a company issues new shares, leaving existing holders with a smaller percentage of the company1. When new tokens are released, each existing token is a smaller slice of the total in the same way.
Worked example
Market cap versus FDV
Token ABC trades at 2.00 dollars. 100 million coins circulate, but the maximum supply is 1 billion.
Market cap = 2.00 × 100,000,000 = 200 million dollars.
FDV = 2.00 × 1,000,000,000 = 2 billion dollars.
Only 10% of the eventual supply is trading. For the price to stay at 2.00 once all coins exist, buyers would have to value ABC at ten times its current market cap. Illustrative numbers. Calculated in code.
A wide gap between market cap and FDV is therefore a prompt to find out when the remaining coins are scheduled to be released and to whom. Look for that schedule in the project's own documentation; if you cannot find one, that is itself worth noting.
Why can market cap be misleading?
The multiplication values every coin at the price of the most recent trade, even though only a tiny fraction of coins changed hands at that price. So market cap is not the amount of money people have put in, and it is not what holders could get if they all sold at once.
Worked example
How one trade can move market cap
Token ABC has 100 million coins in circulation. A single buyer lifts the last traded price from 2.00 to 2.20 dollars. Market cap rises from 200 million to 220 million dollars, a 20 million dollar jump, even though the buyer may have spent far less than that. Illustrative numbers. Calculated in code.
Ownership concentration adds to the problem. An October 2022 report by ESMA, the EU's securities markets regulator, cited estimates that 2% of wallets held 94% of all bitcoins, and noted that such concentration matters for liquidity and for market integrity, since large orders can distort price formation6. The same report warned that, with crypto still largely unregulated, available figures should be treated with caution because comprehensive, reliable data is lacking6. A wallet is not the same as a person, but the point stands: concentrated holdings can move the very price that market cap multiplies.
Finally, two data sites can show different market caps for the same coin if they count supply differently or take prices from different venues. Our guide to how crypto markets work explains why prices vary between venues.
What mistakes do beginners make with market cap?
Common beginner mistakes
Reading a low price as cheap
A one-cent coin with trillions of units can be valued more highly than a coin priced in the thousands. Compare market caps, not unit prices.
Ignoring the supply still to come
If most of the maximum supply is not yet circulating, future releases will increase the number of coins that can trade. Check FDV and the release schedule.
Treating market cap as money invested
It is last price times supply. A thinly traded token can show a large market cap that very little money supports.
Comparing numbers from different sources
Different data sites count supply and choose prices differently. Use one source when comparing, and check its method.
Risk warning
Size is not safety
A large market cap does not make a crypto-asset safe or stable. The SEC has warned that crypto asset securities can be exceptionally volatile and speculative8. Do not invest money you cannot afford to lose, and read our risk disclosure.
Frequently asked questions
Does a higher market cap mean a better investment?
No. Market cap measures size at the latest price, not quality, safety or future returns. It tells you nothing about whether the price will rise or fall.
Can market cap go down even if the price stays the same?
Market cap only changes if the price or the circulating supply changes. If coins are burned or removed from circulation, market cap falls at the same price; if new coins are released, it rises.
Why do stablecoins have large market caps?
A stablecoin aims to trade at about one unit of its reference currency, so its market cap is roughly the number of coins in circulation. It reflects how many tokens have been issued, not price growth.
Is FDV always higher than market cap?
FDV can never be lower, because maximum supply is at least as large as circulating supply. The two are equal only when every coin that can exist is already circulating. If a token has no fixed maximum supply, FDV has no defined value.
Where does the circulating supply number come from?
It is an estimate. Data sites and projects work it out from blockchain records and project disclosures, and methods differ, which is one reason ESMA urges caution with crypto figures6.
The bottom line
Market cap is price times circulating supply: a fast way to compare the size of crypto-assets, and nothing more. Check which supply figure is being used, compare it with FDV to see how many coins are still to come, and remember that the number values every coin at the last trade rather than measuring money invested.
Sources
- Glossary (Resources for Small Businesses) — U.S. Securities and Exchange Commission Primary source
- Glossary: Market Capitalization — Investor.gov, U.S. Securities and Exchange Commission Primary source
- Crypto-Assets: Implications for financial stability, monetary policy, and payments and market infrastructures (Occasional Paper No. 223) — European Central Bank, 2019 Primary source
- Bitcoin Core source code: src/consensus/amount.h (COIN and MAX_MONEY) — Bitcoin Core project, 2026 Primary source
- Bitcoin Core source code: src/validation.cpp (GetBlockSubsidy) — Bitcoin Core project, 2026 Primary source
- Crypto-assets and their risks for financial stability (ESMA50-165-2251) — European Securities and Markets Authority, 2022 Primary source
- Bitcoin: A Peer-to-Peer Electronic Cash System — Satoshi Nakamoto, 2008 Primary source
- Exercise Caution with Crypto Asset Securities: Investor Alert — Investor.gov, U.S. Securities and Exchange Commission, 2023 Primary source
How we checked this page: every figure above links to the numbered source it came from. Spotted an error? Tell the desk — see our editorial policy.
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