How Market Cap and Supply Work in Crypto

Two coins can trade at wildly different prices and still be, in a meaningful sense, similar in size, or trade at nearly the same price and be nothing alike. The reason is supply. Understanding how market cap is calculated, and what the various supply figures actually mean, turns a single misleading number (price) into a much more useful picture.

What Market Cap Actually Measures

Market capitalisation is calculated with a simple formula: price multiplied by circulating supply. As a purely hypothetical example, a coin trading at a hypothetical $2 with 500 million coins in circulation would have a hypothetical market cap of $1 billion. Change either number and the market cap changes with it, which is precisely why price by itself is not a measure of size. A coin priced at a fraction of a cent can have a larger market cap than a coin priced in the hundreds of dollars, depending entirely on how many coins exist.

Circulating, Total, and Max Supply

Crypto data sites typically show three different supply figures, and mixing them up is one of the most common beginner errors:

• Circulating supply — coins that are currently available and moving in the market. This is the figure used in the standard market cap calculation.
• Total supply — all coins that currently exist, including any that are locked, reserved, or not yet in circulation.
• Max supply — the maximum number of coins that will ever exist, if the protocol has a hard cap. Bitcoin is the best-known example: its protocol enforces a fixed cap of around 21 million coins, released on a fixed schedule roughly every four years through an event called the halving. You can read more on the Bitcoin coin page.

Not every asset has a max supply. Some protocols are designed to issue new coins indefinitely, at a fixed or variable rate, with no hard ceiling. Neither approach is automatically better, it depends on what the protocol is trying to achieve, but it is essential to know which situation you are looking at before drawing conclusions from a price alone.

Fully Diluted Valuation (FDV)

Fully diluted valuation estimates what the market cap would be if the entire max supply (or total supply, for assets with no hard cap) were already in circulation, at the current price. It is calculated as price multiplied by max supply rather than circulating supply. As a hypothetical illustration: if that same coin priced at $2 has a max supply of 2 billion but only 500 million are currently circulating, its market cap is $1 billion while its FDV is $4 billion. A large gap between market cap and FDV signals that a substantial amount of supply has yet to enter the market, through unlocks, vesting schedules, or ongoing issuance, which can matter a great deal for how the price might behave as that supply arrives. Reading FDV alongside market cap, rather than looking at either figure alone, gives a fuller picture of how much of a project's eventual size is already reflected in today's price.

Why Price Alone Misleads

Because market cap depends on supply as much as price, comparing two assets by price alone tells you almost nothing about their relative size or history. A coin priced at $0.001 is not automatically "cheaper" or more likely to grow than a coin priced at $500 — the only way to compare them meaningfully is by market cap, and even then, market cap describes the current market's valuation, not a guarantee about the future. A brand new token can also launch with an unusually large headline supply specifically so its price looks small and approachable, which is a marketing choice rather than a meaningful signal about value. Our companion piece on why market cap can be misleading goes further into the ways this single figure can still be distorted, including thin trading and unusual supply structures.

Market Cap and Dominance

Market cap becomes even more useful when compared against the combined market cap of all cryptocurrencies, a ratio commonly called dominance. If one asset's market cap represents a large share of that combined total, that share is described as its dominance. Watching how a single asset's dominance changes over time can say more about shifting market conditions than watching its price alone, since dominance strips out moves that simply reflect the whole market rising or falling together. This is a distinct concept from market cap itself, but it relies on the same underlying calculation and is worth understanding once the basics above are clear.

Reading Supply as Part of Tokenomics

Supply design is one piece of a broader subject called tokenomics: the rules governing how a token is created, distributed, and, in some cases, removed from circulation. Two assets with identical circulating supply today can have very different futures if one has a large amount of locked supply scheduled to unlock over the coming years and the other does not. Reading a project's own documentation for its issuance schedule and unlock timeline is a core part of researching supply properly, rather than relying on a snapshot figure alone.

Where to Find These Figures

Reputable market-data sites display circulating supply, total supply, max supply, and FDV alongside price and market cap for most listed assets, though not every asset publishes all four consistently, particularly newer or smaller projects. When a figure is missing rather than shown as zero, treat it as unknown rather than assuming it means none exists. Cross-referencing a project's own published documentation, particularly its tokenomics page or whitepaper, against the numbers shown on a data site is good practice whenever a decision of any size depends on the answer, since third-party data sites can occasionally lag behind a protocol's actual issuance schedule.

Putting This Into Practice

When you look at any coin on a markets page, get into the habit of checking four things together rather than price in isolation: market cap, circulating supply, max supply (if one exists), and FDV where it is shown. Together, these tell you roughly how large the asset is valued today, how much of its eventual supply is already accounted for, and how much dilution might still be ahead. None of this is financial advice or a signal to buy or sell — it is simply the vocabulary needed to read a coin's numbers accurately instead of being misled by price alone.

A Worked Comparison

Consider two entirely hypothetical coins, Coin A and Coin B, used only to illustrate the mechanics described above. Coin A trades at a hypothetical $10 with 10 million coins circulating, giving a market cap of $100 million. Coin B trades at a hypothetical $0.01 with 50 billion coins circulating, giving a market cap of $500 million. On price alone, Coin A looks ten times more "expensive"; by market cap, Coin B is actually five times larger. Neither number says anything about which is the better asset to hold, that depends on far more than supply, but the example shows concretely why price and market cap answer different questions.