Intro

Lots of people appear to have misconceptions like pondering if x {dollars} move into an asset, its market cap will go up by x {dollars}. In truth, it’s not potential to find out how a lot cash has been put in to an asset based mostly on its market cap, or conversely how a lot a market cap will transfer when some amount of cash flows into or out of the asset.

Price is solely a perform of the present state of the order books throughout all markets that listing the asset.

Consider this: let's say the present worth of BTC on Binance is 50k. What does that basically imply? It merely implies that the very most cost-effective restrict promote order at present on their order books is for 50k. That's what worth means definitionally, proper? Price is simply the quantity you must pay to purchase one thing, so on a CEX worth is at all times merely the present most cost-effective restrict promote.

Example 1: Huge Purchase with No Effect on Market Cap

Let's say that the present worth of BTC on Binance is $50k, and the individual at present prepared to promote at 50k (and who’s thus the individual at present defining the Binance worth of BTC) is a whale who’s providing 1000 BTC at 50k. Let's say I’m a whale purchaser and I’m put in a market order for 999 BTC. Well, I’ll find yourself shopping for all 999 from the whale vendor, leaving them with 1 BTC nonetheless on the market at 50k. Since they’re nonetheless promoting 1 BTC at 50k, the worth of BTC on Binance continues to be 50k. So I simply purchased practically $50 million value of BTC however the worth (and subsequently the market cap) didn't transfer by even a penny.

Example 2: Tiny Purchase with Huge Impact on Market Cap

Now think about one other state of affairs. The present worth of BTC on Binance is 50k, as a result of the present most cost-effective restrict promote is somebody promoting 0.01 BTC on the worth of 50k. Let's say I resolve to purchase 0.02 BTC. Well, half of that can come from the individual promoting 0.01 at 50k, which suggests I’ll eat that vendor. The worth of BTC on Binance will now teleport to regardless of the subsequent most cost-effective restrict order is for (that is the mechanism by which worth goes up when folks purchase). Since BTC may be very excessive liquidity (which suggests a number of restrict orders on the books packed densely throughout the worth spectrum), the following most cost-effective restrict promote after the 0.01 BTC at 50k would most likely be at like 50.00001k. But, for the sake of the instance, let's think about a extra excessive state of affairs by which BTC liquidity is extraordinarily low so the following most cost-effective supply after the 0.01 at 50k is at 50.5k, absolutely 1% dearer. Ok, nicely, I find yourself getting 0.01 BTC at 50k, and one other 0.01 BTC at 50.5k, fulfilling my market order and leaving the worth of BTC on Binance at 50.5k. So, I’ve spent about $1000, however I moved the worth of BTC by 1%, which suggests my buy of $1000 elevated the BTC market cap by practically $10 billion.

Closing Thoughts

Now, I’ve been kind of glossing over the truth that for BTC and most cryptos, they’re listed on many impartial order books without delay (one for every CEX), so an asset technically has as many alternative costs as markets that listing it. So, when you triggered an enormous outsized worth spike on Binance for a scorching second because of a particularly illiquid market, you didn't truly spike "the" worth of BTC by that quantity, you simply spiked the worth of BTC on Binance by that quantity. "The" worth of BTC as reported on one thing like CoinGecko is simply is only a weighted common of the costs in all of the completely different markets. In actuality, all of the issues I’ve described on this put up are taking place independently in each marketplace for one asset like BTC, after which the costs throughout these markets are stored in sync because of arbitrage.

There are additionally markets that listing BTC with out utilizing the order ebook construction. These are known as DEXes (decentralized exchanges), and are the bread and butter of DeFi. If you'd wish to know intimately how costs work with DEXes and liquidity swimming pools, you may learn my put up on that subject here. For the context of this put up, although, all you could know is that DEX costs are stored according to CEX costs because of arbitrage merchants buying and selling liquidity swimming pools in opposition to CEX costs. So, principally, CEX order books do 99% of the first shifting of costs, after which DEX costs are principally a mirrored image of CEX costs.

There you’ve got it, that’s how costs truly transfer. It's not potential to understand how a lot a given purchase or promote will transfer a market cap until you recognize the precise state of the order books at that second on the change you're promoting on, in addition to the quantity of arbitrage friction between all markets.

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Edit: A bunch of individuals have introduced up a sure level, so I feel I ought to tackle it. As many commenters have stated, the worth generally used as worth on CEX worth feeds/charts and oracle feeds and whatnot is the final worth the asset traded at, not the at present lowest restrict promote (although these two values are normally very shut and infrequently the very same).

Well, I concede that that is technically true, however right here's the factor. On any CEX, there are literally 3 completely different ideas of worth: final, bid, and ask (some CEXes will present you all 3 of these values, some received't). "Last" is solely the final worth that was traded at, and is what you usually will see listed on the CEX as the worth, as many commenters have identified. "Bid" is the highest-priced restrict purchase order at present on the books, and is the worth you’ll promote at when you click on "market sell". "Ask" is the lowest-priced restrict promote order at present on the books, and is the worth you’ll purchase for when you click on "market buy". Ask worth is the form of worth that I’m referring to on this put up.

All 3 of those costs are usually very shut; the "bid" and the "ask" are at all times separated by the "spread", and the "last" simply pops forwards and backwards between the bid and the ask relying on what the final market order was (a purchase or a promote).

I personally suppose the ask worth is essentially the most smart worth to think about "the" worth in a given market, as a result of the ask is what you pay when you market purchase; it’s how a lot it would value you to purchase the asset from the market. For instance, if the final worth is 50k, and subsequently the worth feed exhibits 50k, however the ask (lowest restrict order) is 49k, and then you definately click on "market buy", you may be shopping for at 49k, not the 50k final worth.

So, whereas CEXes have a tendency to point out the "last" on their worth charts and feeds, the "ask" is what you truly pay once you purchase.

Anyway, I notice that I’ve triggered some confusion with this ambiguity, so thanks for pointing that out everybody.

Someone please appropriate me if I’m flawed, however I don't consider this distinction adjustments something basic about what I described in my put up.