Stablecoins explained: USDC vs USDT vs the rest
Most crypto swings in price. Stablecoins are the exception by design. A stablecoin is a token built to hold a steady value, almost always one US dollar, and it is the quiet plumbing that a huge share of the crypto market runs on.
- A stablecoin aims to stay worth about $1, so you can hold value in crypto without the price swings.
- The biggest, USDT (Tether) and USDC (Circle), are backed by reserves of cash and short-term government debt.
- Stable does not mean risk-free. Backing quality matters, and coins that try to hold their peg with clever math rather than real reserves have failed badly before.
What they are for
Imagine wanting to step out of a volatile position without cashing all the way back to a bank. Stablecoins let you park value in something worth roughly a dollar while staying inside crypto, ready to move again in seconds. They are used to trade, to send money across borders quickly and cheaply, and increasingly to earn yield. In practice, a large portion of all crypto trading is priced against stablecoins rather than actual dollars.
The main types
There are three broad kinds. Fiat-backed stablecoins, the largest category, are meant to hold one real dollar or equivalent in reserve for every token issued. USDT from Tether and USDC from Circle are the two giants here, and USDC in particular is known for a more transparent, regulated approach to its reserves. Crypto-collateralized stablecoins, such as DAI, are backed by other crypto locked up as collateral, usually more than one dollar's worth per token to absorb price swings. Algorithmic stablecoins try to hold the peg using supply-and-demand rules and little or no hard backing, and they are the riskiest of the three.
Why "stable" has limits
A stablecoin is only as trustworthy as whatever stands behind it. For fiat-backed coins, the key questions are whether the reserves genuinely exist, what they are held in, and whether the issuer can be audited. Even solid stablecoins can briefly slip from their peg during moments of stress, which is why the quality of the backing matters so much. Algorithmic designs carry the sharpest risk: the most infamous example collapsed in 2022, wiping out tens of billions of dollars in days when confidence broke and the math could not hold the price. The lesson stuck: a peg held by belief alone is fragile.
How to use them wisely
For most people, sticking to the largest, most transparent fiat-backed stablecoins is the sensible default. Understand who issues the coin and what backs it before you hold a large amount. Be cautious of any lesser-known stablecoin offering unusually high yields to attract deposits, because that reward has to come from somewhere. And remember that holding a stablecoin still means trusting an issuer or a protocol, so it is not the same as cash in an insured bank account.
Where to go next
Stablecoins are the fuel for a lot of DeFi, so that guide is a natural next read. And if you are moving real money around, our piece on spotting scams is worth your time.