Comparing prices across sites
- Author
- CRYPTO PORT Editorial
- Published
- Updated
- Reading time
- 5 min
In short
The same asset shows different prices on different data sites and exchanges, because they aggregate different venues, weight them differently and convert currencies differently. The point of comparing sources is not to find the one true price but to understand how far a quoted price sits from the price you could actually trade at.
Key points
- Read in order: methodology, which venues, currency conversion, then your own order book
- An index price is usually a weighted average across venues, not a price you can fill at
- In thin books, the quoted price and the fill price diverge sharply
- A gap between sites is not, by itself, an opportunity
Definition
Checking the price of the same asset across several data sites and exchanges, in order to understand why they differ and how they relate to the price you would get.
Start with how the number is built. Most data sites publish an index aggregated from several exchanges, and the venues included, the weighting and the outlier rules differ by provider — often documented on a methodology page. Different methods give different numbers; neither is wrong.
Then look at which venues feed it. An index built from large offshore exchanges and one that includes Japanese venues will differ at the same moment. Japanese prices trading above offshore ones is not unusual, and both local supply and demand and the exchange rate contribute. A yen figure is usually a dollar price converted at some rate, and which rate, sampled when, moves the result.
Now look at the order book on the venue you actually use. This matters most. Even with identical headline prices, the spread and the depth determine what you fill at. In a brokerage-style product the cost is built into the quoted price, so comparing headline numbers hides it entirely. Look at an order book and see how far the price moves for your intended size.
Finally, how to read a gap. People see differences between sites or venues and think of arbitrage, but transfer times, withdrawal fees and limits, verification requirements and the price moving back all sit in between — and are usually larger than the gap itself. A price difference describes a fragmented market; it is not information designed to be acted on.
Watch out for
- · Do not treat cross-site gaps as an opportunity; transfer time, fees and limits sit in the way
- · Brokerage-style quotes embed the spread, so they do not compare directly with an index
- · Being listed on a price site says nothing about an asset's legitimacy or safety
Frequently asked questions
Which site has the correct price?
There is no single correct one. Each is a differently defined figure computed by its own published method. The price that matters in practice is the book on the venue where you place the order; data sites are for a rough sense of level.