USDSvsU
Sky Dollar vs United Stables — side-by-side comparison of supply, chains, backing, and peg data.
Side-by-side
USDS — Sky Dollar
U — United Stables
30-day peg stability dotted line = target · both charts share one scale
What the last 30 days show
Over the last 30 days USDS supply moved -11.1% and U +17.4% — U grew faster. USDS held the tighter band: worst deviation 4 bps against 9 bps.
Key differences
- USDS is roughly 5.5× larger than U by USD circulation value ($6.70B vs $1.21B).
- USDS ranks #3 while U ranks #15 among all tracked stablecoins.
- Both are pegged to the same currency (USD), so they compete directly for the same use cases.
- Both are crypto-backed stablecoins, so the mechanism is not what separates them.
- Reserves differ — USDS holds backed by dai/usdc, U holds stablecoin basket.
- USDS is deployed on 7 chains — much broader coverage than U's 3.
- Primary chain differs — most USDS supply lives on Ethereum, while most U supply is on BSC.
Full comparison table
| Metric | USDS | U |
|---|---|---|
| USD circulation value | $6.70B | $1.21B |
| Rank (by USD value) | #3 | #15 |
| Peg | USD | USD |
| Mechanism | crypto-backed | crypto-backed |
| Backing | Backed by DAI/USDC | Stablecoin basket |
| Chains deployed | 7 | 3 |
| Primary chain | Ethereum | BSC |
| Issuer | Sky | — |
| CoinGecko | View → | View → |
Frequently Asked Questions
What's the main difference between USDS and U?
Both track USD, so they compete for the same use cases. USDS holds backed by dai/usdc; U holds stablecoin basket. USDS ranks #3 by USD value and U ranks #15.
Which is bigger, USDS or U?
USDS is larger, with $6.70B in circulation vs $1.21B for U. That's roughly 5.5× the size.
Is USDS safer than U?
Neither is inherently safer. Safety turns on reserve composition, issuer transparency, redemption rights and regulatory oversight — none of which this page audits. Both use a crypto-backed model, so the difference sits in the issuer and the reserves rather than the design. Read each issuer's most recent reserve attestation before choosing.
Can I convert between USDS and U?
Yes. USDS and U both trade on major centralized and decentralized exchanges. Since both track USD, the exchange rate is typically very close to 1:1. Direct swap protocols on Ethereum, Solana, and other chains offer the tightest spreads.
Should I choose USDS or U?
The right choice depends on your use case. Consider: which chain do you need? USDS is available on 7 chains and U on 3. What backing do you prefer? What's your integration surface (exchanges, DeFi protocols, payment providers)? Both have deep liquidity, so market cap alone shouldn't decide it.