USD stablecoins

Why this currency

The dollar is the only currency where the peg is not the interesting question. Almost every stablecoin ever issued references it, the largest are among the most liquid assets in crypto, and a reader arriving here already knows the peg holds most of the time.

The interesting question for the dollar is what is actually behind each token, and the answer varies far more than the shared ticker convention suggests. Three quite different instruments are listed together in the roster below, and the difference between them matters more than any difference in peg performance.

Sources: Circle, transparency page, Tether transparency page

Market structure

The first group is the fiat reserve issuer. A company takes dollars, holds them in cash and short term instruments, and issues a token redeemable at par. USDC, USDT, PYUSD, USDP and RLUSD sit here. This is the only group where a reserve examination is a coherent idea at all, because it is the only group with an offchain balance for an outside party to count.

The second is the tokenised treasury product. BUIDL, OUSG, USYC and TBILL hold government securities and pass their yield through to holders. These are investment products with a stablecoin's interface, and their stability comes from the asset rather than from a redemption promise.

The third is the protocol dollar. DAI, USDS, crvUSD, GHO and frxUSD hold their peg through collateral and incentives, and the synthetic dollars such as USDe do it through hedged positions. Their backing is already visible onchain, so nothing about them is attestable in the sense the first group is, and nothing needs to be.

A disclosure rating built for the first group says very little about the third. On this map the tier on a coin describes what its issuer has published about reserves, which is why a protocol dollar with excellent onchain transparency and no attestation is a different case from a fiat issuer that publishes nothing.

Sources: Circle, transparency page, Tether transparency page

What this map tracks

DIA reads dollar stablecoin supply from contract state on the chains it indexes. For this currency the difference between those two sets matters more than anywhere else on the map, because the largest dollar coins are deployed across the most chains and are the ones DIA currently reads least completely. Where a page shows fewer chains than a coin is deployed to, the figure is a floor rather than a total. Treat any dollar coin's supply here as a lower bound unless the page accounts for every chain its issuer documents, because on this currency more than on any other it frequently does not, and the shortfall is not always visible from the page itself. The per chain view is the whole point, because most of these tokens live on many chains at once and a single headline figure hides where the supply sits and whether the bridges between deployments would make a naive total double count.

Where a coin's deployments cannot all be read, DIA reports what was read and does not estimate the remainder. Where bridge topology makes a cross chain sum meaningless, no sum is shown.

On reserves, the honest summary for the dollar is that publication is common and examination is rarer. A daily circulation page and a signed examination report are different documents, and only one of them involves anyone outside the issuer counting anything. Each coin page records which of the two exists, who signed it if anyone did, and what the signing firm explicitly left outside its opinion.

Sources: Tether transparency page, Circle, transparency page

Common questions