What Are Stablecoins? How They Work and Types

A stablecoin is a cryptocurrency designed to hold a steady price by tying its value to an outside reference, most often the U.S. dollar. Other references include another fiat currency or a commodity such as gold. The issuer or protocol keeps the price close to that peg in one of two ways: by holding reserve assets that back the coins in circulation, or by running rules that expand and shrink the supply. A dollar stablecoin aims to be worth $1.00 at all times. It moves on a blockchain like any other token, but its price is not supposed to rise or fall.

Why Stablecoins Were Created

Most cryptocurrency prices move too much to work as money. Bitcoin went from around $6,000 in March 2020 to more than $63,000 in April 2021, then lost nearly half its value over the following two months. Moves of more than 10% within a few hours have happened many times. Traders welcome that volatility. Buyers and sellers who simply want to exchange value do not.

A merchant who accepts a volatile coin can lose money if the price drops before the coin is converted, and a buyer who spends it can give up gains if the price rises. To work as a medium of exchange, an asset that is not legal tender needs predictable short-term purchasing power. In major fiat currencies, even a 1% move in a day is unusual.

Stablecoins offer that predictability while keeping what crypto users rely on: transfers that settle on-chain at any hour, self-custody in a wallet, and compatibility with exchanges and smart contracts.

How Stablecoins Work

Every stablecoin needs a reason for its market price to return to the peg when it drifts. Reserve-backed coins usually get it from minting and redemption.

1. A customer sends $1 to the issuer, and the issuer mints one new coin. The dollar goes into reserves.
2. A holder returns one coin to the issuer and receives $1 back. The issuer burns the coin.
3. Because these two routes exist, traders can profit whenever the market price moves away from $1, and their trades push it back.

Hypothetical example. A dollar stablecoin trades at $0.98 on an exchange after a wave of selling. An arbitrageur with redemption access buys 100,000 coins for $98,000 and redeems them with the issuer for $100,000. Ignoring fees and transfer time, that is a $2,000 profit. The buying lifts the market price toward $1. If the coin instead trades at $1.02, the arbitrageur mints new coins at $1 and sells them above $1, which adds supply and pulls the price down.

This only works if the reserves exist and are liquid, redemption stays open, and traders believe both will hold. Redemption is often limited to verified customers and may carry minimum amounts or fees, so ordinary holders rely on arbitrageurs to keep the exchange price in line.

For a dollar stablecoin, the useful number is how far the price sits from $1.00. Gaps of a fraction of a cent reflect normal trading friction. A sustained gap of several cents suggests the market doubts redemption or reserves.

Types of Stablecoins

The four types are grouped by what stands behind the peg.

Fiat-Collateralized Stablecoins

These coins hold reserves in a fiat currency or close equivalents, such as bank deposits and short-term government debt. Custodians hold the reserves, and accounting firms review them on a regular schedule. Tether (USDT), USD Coin (USDC) and TrueUSD (TUSD) are dollar-backed examples, each issued at parity with the U.S. dollar. Tether has been the largest stablecoin by market capitalization and ranks among the largest cryptocurrencies of any kind.

The design is simple, but it is centralized. Holders depend on the issuer’s honesty, the quality of its reserves, its banking partners and its custodians. Issuers of these coins can also freeze tokens at specific addresses, which a bank-like company may be required to do and which a fully decentralized asset could not do.

Commodity-Backed Stablecoins

Commodity-backed coins are tied to a physical asset such as gold or oil. The issuer holds the commodity, usually through a third-party custodian, or holds related investments. Tether Gold (XAUt) represents gold held in reserve, reportedly with a custodian in Switzerland, and its terms let a holder who completes redemption ask for physical delivery of a gold bar there, subject to the fees in effect at the time.

A commodity-backed coin is stable against the commodity, not against the dollar. If gold falls 10%, a gold token falls with it.

Crypto-Collateralized Stablecoins

These coins are backed by other cryptocurrencies held in smart contracts. Because the collateral is itself volatile, they are overcollateralized: the collateral is worth more than the stablecoins issued against it.

The core ratio is:

Collateralization ratio = value of collateral ÷ value of stablecoins issued

Hypothetical example. Cryptocurrency worth $2 million locked to issue $1 million of stablecoins gives a 200% ratio. The collateral can lose half its value before it is worth less than the coins it backs. Protocols set a minimum ratio, and when a position falls below it, the system sells or auctions the collateral (a liquidation) to cover the debt before it goes underwater.

Dai (DAI), originally created by MakerDAO, is pegged to the U.S. dollar and backed by Ethereum (ETH) and other crypto assets. Coins like this are a core part of DeFi, where users lock collateral to borrow stablecoins without a bank. The main risks are a crash too fast for liquidations to keep up, faults in the smart contracts, and the composition of the collateral. If a protocol accepts centralized stablecoins as collateral, it partly takes on their risks too.

Algorithmic Stablecoins

Algorithmic stablecoins may or may not hold reserves. What sets them apart is that they keep the peg by controlling supply with a preset formula run by software. A common design pairs the stablecoin with a second, freely floating token. When the stablecoin trades below $1, users can burn it and receive $1 worth of the sister token. When it trades above $1, the process runs the other way.

TerraUSD (UST) showed what happens when demand for the sister token fails. On May 11, 2022, UST fell more than 60% below its dollar peg as its partner token, Luna, dropped more than 80% overnight. Holders redeemed UST for Luna, the new Luna supply drove Luna’s price lower, and each redemption required minting more Luna. This is often called a death spiral: the mechanism meant to restore the peg sped up the collapse.

How Stablecoins Are Used

• Trading. Many crypto exchanges quote pairs against dollar stablecoins, so traders can move out of volatile positions without converting to cash through a bank.
• Moving value between platforms. A stablecoin can be sent between exchanges and wallets at any hour, with settlement on-chain rather than through bank transfers.
• Payments and remittances. Stablecoins can be sent across borders to anyone with a compatible wallet. The cost depends on the blockchain’s network fee and on the fees to get in and out of local currency.
• DeFi. Stablecoins are used as collateral, borrowed and lent in lending markets, and paired in liquidity pools.
• Holding dollar value. Some users hold them as a dollar-denominated balance outside the traditional banking system.

A pegged coin is not built to appreciate. Any yield on stablecoins comes from lending them out or putting them to work on a platform, and that adds the platform’s own risk.

Risks and Limitations

• Depegging. Any stablecoin can trade below its peg when confidence in reserves, redemption or the mechanism weakens. A peg that held for years can still fail.
• Reserve verification. An attestation is a point-in-time check of reserves, while a full audit is a broader examination. Either way, holders rely on third parties to confirm that reserves exist and are liquid, which reintroduces the trust crypto was designed to minimize.
• Counterparty and custody risk. The issuer, its custodians and its banks can fail or be restricted.
• Regulatory change. New rules can affect which coins an exchange may list in a given jurisdiction.

Regulation of Stablecoins

In October 2021, the Bank for International Settlements’ payments committee and the International Organization of Securities Commissions (IOSCO) said that systemically important stablecoin arrangements should follow the international principles for financial market infrastructure such as payment systems and clearinghouses.

In the European Union, the Markets in Crypto-Assets Regulation (MiCA, Regulation (EU) 2023/1114), adopted in 2023, regulates algorithmic stablecoins strictly. For other stablecoins, it requires reserve assets to be held in custody by a third party, to be liquid, and to match coins in issue at a 1:1 ratio.

In the United States, President Donald Trump signed the GENIUS Act into law in 2025. It requires issuers to hold liquid reserves such as U.S. dollars or short-term Treasuries and to disclose the composition of their reserves every month. It also sets marketing rules, including a ban on misleading claims that a stablecoin is federally insured or legal tender.

Stablecoins vs. Similar Concepts

Stablecoin vs. Bitcoin. Bitcoin’s price floats freely with supply and demand and is not pegged to anything. Stablecoins exist as a low-volatility alternative. Compare Bitcoin’s history on the Bitcoin monthly returns page with a stablecoin’s price, which stays close to its peg when it works as designed.

Stablecoin vs. CBDC. A central bank digital currency is issued by a central bank and is a direct liability of that bank. A stablecoin is issued by a private company or a protocol, and its value depends on that issuer’s reserves or mechanism.

Stablecoin vs. bank deposit. A dollar in a bank account is a claim on a regulated bank and may be covered by deposit insurance. A dollar stablecoin is a claim on the issuer, or on a smart contract, and has no deposit insurance.

Which Stablecoin Is Best?

No single stablecoin is best for every purpose, because the right choice depends on which risk you are willing to carry. Choosing among coins comes down to a few questions:

• What backs the coin?
• Who holds those assets, and how often are they reported?
• Who can redeem, and on what terms?
• Is the coin permitted under the rules where you live?

BitcoinBTC$64,908EthereumETH$1,817SolanaSOL$71.49

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