Short answer: a stablecoin is a crypto token designed to hold a steady value, almost always one US dollar. USDT and USDC do it by holding reserves of cash and short-term treasuries; DAI does it by over-collateralising with other crypto assets. The mechanism behind the peg determines what can go wrong.
Why stablecoins exist
Blockchains settle in minutes, worldwide, without banking hours. What they lacked was a unit that does not move 8% before the transfer confirms. Stablecoins supplied it, and became the default settlement asset: traders park in them, remittances move through them, and most trading pairs are quoted against them.
Three designs, three risk profiles
| Design | How the peg holds | Examples | Main risk |
|---|---|---|---|
| Fiat-backed | Reserves of cash and short-term government debt, redeemable by large clients | USDT, USDC | Issuer, custodian and regulatory risk |
| Crypto-collateralised | Over-collateralised crypto locked in smart contracts | DAI | Collateral crash, liquidation cascades, contract bugs |
| Algorithmic | Supply expands and contracts by protocol rules | Historic designs, largely discredited | Reflexive collapse — repeatedly demonstrated |
The 2022 failure of a large algorithmic stablecoin, which unwound to near zero within days, is the reason serious users now treat "how is it backed" as the first question rather than a technicality.
USDT vs USDC in practice
- Liquidity and reach. USDT dominates volume, especially outside the US, and is available on the widest range of chains. If you need to move value in a hurry to an arbitrary counterparty, it is the path of least friction.
- Reporting and regulation. USDC has positioned itself around regulated issuance and detailed attestations, which many institutions prefer.
- Chain availability. Both exist on all major networks, but USDT's presence on Tron makes it the default for low-cost transfers.
- Depegs. Both have briefly traded below a dollar during market stress and both recovered. Brief deviations are normal; a sustained one is a signal.
Where DAI is different
DAI is issued by a decentralised protocol against collateral locked in smart contracts, rather than by a company holding bank deposits. That removes the "one issuer can freeze an address" concern and replaces it with smart-contract and collateral risk. Over time DAI has also come to hold centralised stablecoins among its collateral, which softens the distinction in practice.
Real risks worth knowing
- Issuer risk. Fiat-backed tokens are a claim on a company. Reserve quality and jurisdiction matter.
- Freezing. Centralised issuers can and do blacklist addresses at the request of law enforcement.
- Chain risk. Your USDT is only as available as the chain it sits on.
- Yield is not the coin. Lending your stablecoins for a return introduces the risk of the platform, which is a completely separate decision from holding them.
Practical guidance
- Use stablecoins as a settlement and waiting asset, not as a savings account with yield attached.
- Split across two issuers if the amount is meaningful to you.
- Prefer cheap chains for holding, and convert to the chain you need only at the moment you need it.
- Keep enough of the native gas coin to move funds at any time.
Key takeaways
- A stablecoin is only as stable as the mechanism behind its peg.
- Fiat-backed coins carry issuer risk; crypto-backed coins carry contract and collateral risk.
- Algorithmic designs without real collateral have a poor historical record.
- Diversifying across issuers costs nothing and removes a single point of failure.
You can swap between stablecoins and any other supported asset directly on the Cryptozilla exchange, or read which USDT network to choose before you move funds.
Frequently asked questions
Are stablecoins actually safe?
Major fiat-backed stablecoins have held their peg through several severe market events, but they are corporate liabilities rather than bank deposits and carry no deposit insurance. Treat them as low-volatility, not risk-free.
What is a depeg?
A period when a stablecoin trades away from its target value, usually because of a liquidity shock or doubt about its reserves. Short deviations of a fraction of a percent are routine; a sustained gap indicates a genuine problem.
Can stablecoins be frozen?
Centralised issuers such as Tether and Circle can blacklist addresses, and they do so in response to law-enforcement requests. Decentralised designs are harder to freeze at the token level but carry other risks.
