ChatGPT response to the question “If I buy a dollar of bitcoin, will the market cap of bitcoin rise by a dollar?”:

Great question — and the answer is no, not quite!

If you buy $1 of Bitcoin, the market cap of Bitcoin won’t just rise by $1. Instead, the market cap could increase by much more, depending on the price movement your trade causes.

Here’s why:

📌 Market Cap Formula:

Market Cap = Current Price × Total Circulating Supply

When you buy $1 worth of Bitcoin:

• You’re buying a tiny fraction of a Bitcoin at the current market price.

• But if your buy (and others like it) causes the price to tick up, even slightly…

• Then that new higher price gets applied to all the circulating Bitcoins, not just the one you bought.

So even a small trade can cause a large change in market cap, especially in illiquid or thin markets.

Example:

• Suppose Bitcoin is $50,000 and there are 19 million BTC in circulation.

• Market cap = 50,000 × 19,000,000 = $950 billion

Now say your $1 buy pushes the price up by just $1 (to $50,001):

• New market cap = 50,001 × 19,000,000 = $950.019 billion

• That’s a $19 million increase in market cap — from just a $1 trade!

Of course, in reality, a single $1 trade probably won’t move the price unless liquidity is super low. But this shows how the last traded price drives market cap.

TL;DR:

A $1 buy doesn’t increase market cap by $1 — market cap changes are tied to price changes, not the size of individual trades.

Let me know if you want an analogy — there’s a fun one involving paintings and auctions.