A stablecoin is a cryptocurrency designed to hold a steady value, usually one unit equal to one US dollar. Unlike Bitcoin or Ether, whose prices move around throughout the day, a stablecoin aims to stay at or very close to its target price. That stability is the whole point. It lets people hold and move digital money without watching the value swing between the time they receive it and the time they spend it.
The target price is called the peg. Most stablecoins are pegged to the US dollar, though versions exist for the euro and other currencies. When a stablecoin trades at exactly $1.00, the peg is holding. When it drifts to $0.99 or $1.01, the market and the issuer have mechanisms meant to pull it back. How well those mechanisms work depends on the type of stablecoin.
How the peg is meant to hold
There are three broad designs, and they keep the peg in different ways.
Fiat-backed stablecoins are the most common. For each token in circulation, the issuer claims to hold one dollar (or an equivalent asset such as a short-term government bond) in a bank or custody account. If someone wants out, they redeem the token for a real dollar, and the token is removed from circulation. The reserve is what backs the price. USDT (Tether) and USDC (Circle) work this way. The main thing a holder is trusting here is that the reserves are real, sufficient, and available, which is why reserve reports and audits get so much attention.
Crypto-collateralized stablecoins hold other cryptocurrencies as backing instead of cash. Because crypto prices move, these systems require more collateral than the value of the coins they issue. A user might lock $150 worth of Ether to mint $100 of a dollar-pegged coin. The extra $50 is a buffer. If the collateral falls in value, the system can sell some of it automatically to keep the coin fully backed. DAI is the best-known example. The trade-off is that this design is more complex and depends on the backing crypto not crashing faster than the system can react.
Algorithmic stablecoins try to hold the peg through software rules and supply adjustments rather than holding reserves of equal value. They expand or shrink the token supply to push the price back toward the target. Several have failed, and the collapse of TerraUSD in 2022 wiped out tens of billions of dollars in a few days. They exist, and anyone reading about stablecoins should know the category is there, but they carry a different and higher risk than the reserve-backed kinds. For a fuller technical overview, the stablecoin reference page covers each design in more depth.
Why they get used for payments
The reason stablecoins matter for everyday payments comes down to speed, cost, and reach.
A stablecoin transfer settles on a blockchain, often in seconds or a couple of minutes, and it works the same whether the money is going across the street or across the world. A traditional international bank transfer can take days and pass through several intermediaries, each taking time and a cut. Sending $500 of a stablecoin might cost a network fee of a few cents to a couple of dollars, depending on which blockchain it runs on, with no separate charge based on the amount being sent.
That flat, small cost is attractive for a few concrete uses. Workers sending money home can avoid remittance fees that often run 5% or higher. Freelancers billing clients in another country can get paid without waiting on wire transfers. Businesses can settle with suppliers outside normal banking hours, since blockchains do not close on weekends or holidays.
Stablecoins also give people in countries with high inflation a way to hold dollars without a US bank account. If the local currency is losing value quickly, holding a dollar-pegged token can preserve buying power, and it only needs a phone and an internet connection.
What to keep in mind
A stablecoin is only as reliable as the thing backing it. A fiat-backed coin depends on the issuer actually holding the reserves it claims. A peg can break, briefly or permanently, and when it does, holders can lose money. USDC itself slipped to about $0.87 for a weekend in March 2023 when one of its reserve banks failed, then recovered once the funds were confirmed safe.
Used with those limits in mind, stablecoins give ordinary people a fast, low-cost way to move dollars. That practical function, more than any technology story, is why they have grown into one of the most used parts of the crypto economy.