Stablecoins explained

USDC, USDT, DAI — the rails that keep crypto trading.

TL;DR

Stablecoins are crypto tokens designed to maintain a stable price — usually pegged to the US dollar. They're the rails that let traders move in and out of risk without leaving crypto.

Why they exist

Crypto markets trade 24/7 and most aren't paired against fiat directly. Stablecoins let you sell BTC at 3am Sunday without wiring money. They also dominate DeFi as the unit of account.

Three flavours

Stablecoins maintain their peg in fundamentally different ways.

→Fiat-backed: USDC, USDT — each token is backed 1:1 by dollar reserves (audited, mostly). Centralised.
→Crypto-collateralised: DAI — backed by overcollateralised ETH and other crypto. Decentralised but capital-inefficient.
→Algorithmic: USDe, formerly UST — maintain peg via arbitrage / market mechanisms. History of breaking (Terra/Luna collapse).

Risks every trader should know

Stablecoins are not all created equal — and they're not actually risk-free.

→Reserve risk: is the issuer really holding what they claim?
→Peg risk: a 1% deviation may not seem like much but can be catastrophic when leveraged
→Regulatory risk: jurisdictions can freeze or restrict centralised stablecoins
→Smart contract risk: decentralised stablecoins can be exploited

Worked example

USDC vs USDT vs DAI

Compare the three most-used stablecoins.

1USDCIssued by Circle. Backed by cash + short-duration Treasuries. Monthly attestations.
2USDTIssued by Tether. Largest by market cap. Reserve composition has been disputed historically.
3DAIIssued by MakerDAO. Backed by overcollateralised crypto plus some real-world assets. Fully on-chain governance.
4Typical usePair with high-volume crypto on every major exchange.

Takeaway

USDC is the institutional default. USDT has the deepest liquidity. DAI is the decentralised option for users who don't want to trust an issuer.

Common mistakes

What to avoid

!Treating all stablecoins as identical — reserve quality varies dramatically
!Holding large amounts on a single exchange or in a single stablecoin
!Trusting algorithmic stablecoins after the Terra/UST collapse showed they can go to zero overnight
!Ignoring chain risk — USDC on Solana is different from USDC on Ethereum mainnet

Self-check

Test yourself

Q1What's the main difference between USDC and DAI?+

USDC is centralised and backed by dollars; DAI is decentralised and backed by overcollateralised crypto.

Q2Why are algorithmic stablecoins riskier than fiat-backed ones?+

They rely on market mechanisms that can fail during stress; there's no underlying asset to redeem.

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