Stablecoins Explained: Fiat-Backed, Crypto-Backed and Algorithmic
Stablecoins explained: how fiat-backed, crypto-backed and algorithmic stablecoins hold their peg, what they are used for and the risks of each type.
Stablecoins are cryptocurrencies designed to hold a steady value, usually one US dollar, and they come in three main types: fiat-backed coins backed by cash and government bonds held by a company, crypto-backed coins backed by more crypto collateral than the stablecoins issued, and algorithmic coins that try to hold the peg through code and market incentives with little or no collateral. Each type keeps its peg differently and fails differently.
Stablecoins are the plumbing of crypto markets. Traders use them to park value without leaving crypto, DeFi protocols use them for lending and liquidity, and people in some countries use them to hold dollars. Knowing which kind you hold tells you what could go wrong.
Why Stablecoins Exist
Most cryptocurrencies are volatile. That makes them hard to use for payments, accounting or lending. Stablecoins solve this by tracking a reference asset — most often the US dollar, sometimes the euro or gold — while still moving on blockchains 24 hours a day. If you want to go further, read How to Store Stablecoins Safely.
Common uses include:
- Trading: a stable unit for pricing and for moving between positions.
- DeFi: borrowing, lending and providing liquidity.
- Transfers: sending dollar value across borders quickly.
- Savings in unstable economies: holding a dollar-linked asset where the local currency is weak.
Type 1: Fiat-Backed Stablecoins
A company holds reserves — cash, bank deposits, short-term government bonds — and issues tokens against them. Verified customers can redeem tokens with the issuer, and arbitrage between the market price and redemption value keeps the price near the peg. Related reading: DAI vs USDC.
Examples include Tether (USDT) and USD Coin (USDC).
Strengths: simple to understand, deep liquidity, usually very close to the peg.
Risks: you depend on the issuer's honesty and reserves, on its banks, and on regulators. Issuers can freeze tokens at specific addresses. In March 2023, USDC briefly traded well below a dollar after its issuer disclosed that part of its reserves were held at Silicon Valley Bank, which had failed; the peg recovered once those deposits were secured. Our article on USDT vs USDC compares the two largest issuers.
Type 2: Crypto-Backed Stablecoins
Users lock crypto as collateral in smart contracts and mint stablecoins against it. Because crypto is volatile, positions must be over-collateralized — for example, locking more than a dollar of ETH for each dollar of stablecoins. If collateral falls too far, the position is liquidated to protect the system. For background on the project itself, see Ethena USDe (USDe) explained.
DAI, created by MakerDAO (now Sky), is the best-known example. Over time it has also accepted other stablecoins and real-world assets as collateral, which makes it partly dependent on centralized assets too.
Strengths: collateral and positions are visible on-chain, and no single company can unilaterally issue tokens.
Risks: smart-contract bugs, oracle failures, and liquidations that fail in a fast crash. Our guide to over-collateralization explains the mechanics.
Type 3: Algorithmic Stablecoins
Algorithmic stablecoins try to maintain the peg through rules that expand or contract supply, often paired with a second, volatile token that absorbs losses. When the stablecoin trades below a dollar, the system encourages users to burn it in exchange for the second token, and vice versa.
The problem is that this relies on the second token having value. If confidence breaks, holders rush to exit, the volatile token is minted in huge amounts, its price collapses and the peg fails — a "death spiral." That is what happened to TerraUSD (UST) and LUNA in May 2022. See algorithmic stablecoins for the full story.
Newer Designs
Some stablecoins don't fit neatly into the three categories. Ethena's USDe, for example, is described by its issuer as a "synthetic dollar" that holds crypto and offsets price exposure with short derivatives positions. These designs bring their own risks, such as exchange counterparty risk and periods of negative funding rates. Treat novel models with extra caution until they have been tested in severe market conditions.
Comparing the Three Types
| Fiat-backed | Crypto-backed | Algorithmic | |
|---|---|---|---|
| Backing | Cash and bonds held off-chain | Crypto locked on-chain, over-collateralized | Little or none; supply rules and incentives |
| Who you trust | Issuer, banks, auditors, regulators | Smart contracts, oracles, governance | Market confidence and code |
| Transparency | Periodic attestations or reports | Real-time on-chain | On-chain, but value rests on confidence |
| Can tokens be frozen? | Usually yes | Usually not at the token level | Depends on design |
| Main failure mode | Reserve shortfall, bank failure, regulatory action | Collateral crash, bugs, oracle errors | Death spiral |
Stablecoins on Different Networks
Most large stablecoins are issued on several blockchains. Each version has its own contract address, and some versions are bridged by third parties rather than issued directly. Before sending or receiving, confirm that both sides support the same network and that the token's contract matches the issuer's official list.
How to Check a Stablecoin Before Holding It
- 1Identify the type and what backs it.
- 2Read the reserve reports or on-chain dashboards. Look for regular, independent attestations or audits.
- 3Check redemption rights. Who can redeem, at what minimum, and with what fees?
- 4Look at peg history. Has it depegged before, and how quickly did it recover?
- 5Verify the contract address for your network; fake stablecoins are common.
- 6Spread risk. Avoid holding all your savings in one stablecoin or one platform.
Our guide on how to evaluate a stablecoin's backing and redemption goes through this checklist in detail.
Bottom line
"Stable" describes a goal, not a guarantee. Fiat-backed coins ask you to trust a company, crypto-backed coins ask you to trust code and collateral, and algorithmic coins ask you to trust market confidence. Pick stablecoins whose backing you understand, check the network and contract, and don't treat any of them as equivalent to an insured bank deposit.
Frequently asked questions
What is the safest type of stablecoin?
No type is risk-free. Fiat-backed stablecoins depend on the issuer's reserves, banks and regulators; crypto-backed ones depend on smart contracts, collateral and liquidations; algorithmic designs depend on market confidence and have the worst failure record. Evaluate each coin's backing, transparency and redemption rights rather than relying on its category.
How do stablecoins make money for issuers?
Fiat-backed issuers typically earn interest on the reserves they hold, such as short-term government bonds, while holders usually receive no interest. Crypto-backed protocols earn fees from borrowers who mint stablecoins against collateral. Some newer designs generate yield from trading strategies, which adds different risks.
Can a stablecoin lose its peg?
Yes. Stablecoins can trade below their target when confidence drops, reserves are questioned, collateral falls sharply or redemptions are paused. Some have recovered within days, while the TerraUSD algorithmic stablecoin collapsed completely in 2022. A depeg is a key risk to understand before holding large amounts.
Are stablecoins regulated?
Increasingly, yes, but the rules differ by country. Several major jurisdictions have introduced or are introducing licensing, reserve and disclosure requirements for stablecoin issuers. Check your local regulator's guidance, as these rules continue to change.