A crypto screen is a wall of numbers that all look important.
Price. Percentage change. Volume. Little green and red arrows. Most people glance at them and feel informed. Very few know what half of them actually measure. Let's fix that in five minutes.
The short version
- A price belongs to a pair and a venue. BTC-USD on one exchange can differ from BTC-USDT on another.
- The price you see is the last trade, not a promise your next order gets that price.
- "24h change" needs a starting point. A rolling 24 hours and "since midnight" give different numbers.
- Volume needs a unit. It might be counted in coins or in dollars. Always check which.
- A chart tells you what happened, not why. Write those two things down separately.
Every price has an address
BTC-USD means the price of one bitcoin in US dollars, on a specific exchange. Change the exchange or the quote currency and you can get a slightly different number.
And that number is usually the last completed trade. It's history, even if it's only a second old. Your next order fills against whatever is on offer now, which might be a little different, or a lot different on a thin market.
Percentage change: always ask "since when?"
"Down 5%" sounds simple. But down 5% since when?
- Rolling 24 hours compares now with exactly 24 hours ago. MYEX uses this.
- Since midnight compares now with the start of today, in someone's time zone.
- Since the weekly open is different again.
Two sites can show different "24h change" figures for the same coin and both be right. Compare like with like.
Volume: count the unit before you count the number
Volume tells you how much traded over a period. The catch is the unit.
Coinbase Exchange, for example, reports BTC-USD volume in bitcoin, not dollars (Coinbase API documentation). To get a rough dollar figure you multiply by the price. That's what MYEX does, and we label it as approximate, because it isn't the exact dollar value of every trade.
High volume is a decent sign people are trading. It's not proof you can buy or sell big without moving the price. For that, you need order book depth.
Use charts to ask better questions
Here's the habit that separates people who learn from charts from people who get fooled by them:
- Look at more than one time window. A crash on the one-day chart can be a blip on the one-month chart.
- Write down what you see. Direction, range, size of the moves. Just the facts.
- Write down why, separately. And be honest about whether you actually know.
A good note reads: Price rose this week. I haven't established why. That sentence will save you more money than any indicator.
Questions people ask
What does the price shown for a cryptocurrency mean?
It is usually the last completed trade for a specific trading pair on a specific exchange, such as BTC-USD on Coinbase. It is a record of the past, not a guaranteed price for your next order.
Why does the 24-hour change differ between websites?
Sites measure from different starting points. Some use a rolling 24 hours, others use midnight in a particular time zone, so the same coin can show different percentage changes.
Is crypto trading volume measured in coins or dollars?
It depends on the source. Coinbase Exchange reports volume in the base asset, for example bitcoin for BTC-USD. Dollar figures are usually estimates made by multiplying by the price.
Does high trading volume mean a coin is liquid?
Not on its own. Volume shows past trading, while liquidity depends on how much is on offer near the current price right now, which you can see in the order book depth.