Arithmetic on today's supply, not a forecast. It assumes nothing about whether Polkadot could attract that much money.
A coin's market capitalisation is its price multiplied by the number of coins in circulation. Polkadot has 1,700,506,167 DOT in circulation at $1.0190 each, which is $1.73B. Holding that supply still and putting Ethereum's $306.63B in its place gives $180.3146 per DOT.
This is the huge end of the comparison. Polkadot would need $304.89B more than it carries today, and at that size it would be one of the largest assets in the world, crypto or otherwise.
Supply is held still, and in practice it moves: coins are minted, burned and unlocked, and every one of those changes the price a given market capitalisation implies. The figure also says nothing about whether the money exists to buy DOT at that level, which is the part that actually decides a price.
$180.3146 per DOT. That is Ethereum's current market capitalisation of $306.63B divided across the 1,700,506,167 DOT in circulation.
177x. Polkadot trades at $1.0190 today and Ethereum's market cap is $306.63B against Polkadot's $1.73B.
No. It is one division: Ethereum's market capitalisation spread over the supply of DOT that exists today. It assumes nothing about whether Polkadot could attract that much money, and it holds the supply still when in practice supply changes.
It sets it. Market cap is price times circulating supply, so the same $306.63B of market cap spread over more coins gives a lower price per coin. This uses the 1,700,506,167 DOT in circulation now.