Stablecoin Explained: Types, Risks & How the Peg Works
A stablecoin is a cryptocurrency that maintains a fixed value against a reference asset — typically the US dollar. Where Bitcoin and Ethereum fluctuate by double-digit percentages in a day, stablecoins aim to stay at exactly $1, making them usable for payments, lending, and trading without currency risk.
How stablecoins maintain the peg
Fiat-backed
The simplest model: a centralized issuer holds $1 in a bank account for every stablecoin in circulation. USDC and USDT are the largest examples. Holders can theoretically redeem tokens for dollars directly. The risk is counterparty: you are trusting the issuer to actually hold the reserves and not freeze your account.
Crypto-backed
DAI (issued by MakerDAO) maintains its peg by requiring users to over-collateralize loans with crypto assets. To mint $100 of DAI you might need to lock $150 of ETH. If ETH falls and the collateral ratio drops below a threshold, smart contracts automatically liquidate the position. No central issuer is needed — the peg is enforced by code and economic incentives.
Algorithmic
Algorithmic stablecoins attempt to maintain a peg through token supply mechanics rather than collateral. The category has a poor track record — TerraUSD (UST) lost its peg in May 2022 in a cascade that erased ~$40 billion in market cap. Understanding the stability mechanism is one of the most important parts of evaluating any stablecoin whitepaper.
Stablecoins in DeFi
Stablecoins are the primary unit of account in DeFi. Aave's lending markets allow depositing stablecoins to earn yield and borrowing against crypto collateral. DEX liquidity pools (especially Curve Finance) are optimized for stablecoin-to-stablecoin swaps where minimizing slippage matters more than price discovery.
Yield farming strategies often use stablecoins because liquidity provision in stablecoin pools avoids the impermanent loss risk inherent in volatile-asset pairs.
Stablecoin projects on ChainClarity
- Aave — major stablecoin lending and borrowing protocol
- Ethereum — most stablecoins and stablecoin DeFi runs on Ethereum
- Polygon — low-cost chain for stablecoin payments and DeFi
- Chainlink — provides price feeds that underpin stablecoin collateral ratios
Browse all stablecoin projects →
Frequently asked questions
What is a stablecoin?
A stablecoin is a cryptocurrency designed to maintain a stable value against a reference asset — almost always the US dollar, though some peg to gold, euros, or a basket of currencies. Unlike Bitcoin or Ethereum, whose prices fluctuate dramatically, stablecoins aim to stay at exactly $1 so they can be used for payments, lending, and trading without currency risk.
What are the three types of stablecoins?
Fiat-backed stablecoins (USDC, USDT) are backed 1:1 by dollar reserves held by a centralized issuer. Crypto-backed stablecoins (DAI) are over-collateralized with on-chain crypto assets, governed by smart contracts. Algorithmic stablecoins use protocol mechanics (token minting/burning, seigniorage) to maintain the peg without holding direct reserves — the category with the highest historical failure rate.
What caused the UST/LUNA collapse?
TerraUSD (UST) was an algorithmic stablecoin that maintained its peg through an arbitrage mechanism with its sister token LUNA. When large holders began selling UST simultaneously, the arbitrage loop inverted: LUNA was minted at increasing volume to absorb selling pressure, creating hyperinflationary supply that destroyed LUNA's value — which in turn removed the backstop for UST. The peg collapsed in days, wiping out approximately $40 billion in market cap.
Are stablecoins safe?
Fiat-backed stablecoins carry custodial risk (the issuer could fail or freeze assets) and regulatory risk. Crypto-backed stablecoins carry smart contract risk and liquidation risk if collateral prices crash faster than the protocol can respond. Algorithmic stablecoins have the weakest peg guarantees — history shows they are vulnerable to bank-run dynamics. No stablecoin is entirely risk-free.
How do DeFi protocols use stablecoins?
Stablecoins are the primary unit of account in DeFi. Lending protocols like Aave allow depositors to earn yield on stablecoins and borrowers to take stablecoin loans against crypto collateral. DEXs like Curve are optimized specifically for stablecoin swaps. Yield farming strategies often involve stablecoin liquidity provision because it eliminates impermanent loss from price volatility.