Trading Pair
A trading pair is two assets that can be traded directly against each other on an exchange, written like BTC/USDT or ETH/BTC. The price tells you how much of the second asset you pay for one unit of the first.
Base and quote currency
In a pair written as A/B, A is the base currency, the thing you buy or sell, and B is the quote currency, the thing you pay with or receive. If BTC/USDT shows 60,000, one bitcoin costs 60,000 USDT. If ETH/BTC shows 0.05, one ether costs 0.05 bitcoin.
Buying the pair means buying the base and paying in the quote. Selling it means the opposite. Some platforms write pairs with a dash or without a separator, such as BTC-USD or BTCUSDT, but the logic is the same.
Common kinds of pairs
Fiat pairs such as BTC/EUR or BTC/CHF connect crypto to traditional money. Stablecoin pairs such as BTC/USDT or ETH/USDC are the most widely traded on many crypto exchanges because stablecoins move quickly between platforms. Crypto-to-crypto pairs such as ETH/BTC let you trade one coin for another directly and also show their relative strength: if ETH/BTC rises, ether is gaining against bitcoin, regardless of what either does in dollars.
An example
Say you hold USDC and want a small altcoin that is only listed against ETH. You would first trade USDC for ETH on the ETH/USDC pair, then ETH for the altcoin. That is two trades, two fees and two spreads. Some platforms do this routing automatically and show you one combined price, which can hide the extra cost.
Why the pair matters
The same coin can have very different liquidity on different pairs. A token might have deep trading against USDT and very thin trading against EUR on the same exchange, so the spread and slippage you face depend on which pair you choose. Prices also differ slightly between USDT, USDC and fiat pairs, and if a stablecoin loses its peg, every pair quoted in it is affected. When reading charts, it helps to check the pair: a coin can be up against the dollar and down against bitcoin at the same time.
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Frequently asked questions
What does BTC/USDT mean?
It is the market for trading bitcoin against the stablecoin Tether. The price shows how many USDT one bitcoin costs.
Which currency is the base in a trading pair?
The first one. In ETH/USDC, ETH is the base you buy or sell and USDC is the quote currency you pay or receive.
Why can't I trade every coin against euros or francs?
Exchanges list only pairs with enough demand. Smaller coins are often listed only against a stablecoin, BTC or ETH, so you may need an extra trade.
Related terms
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