Etherscan Cards

Bringing DeFi Yield Insights to the World’s Most Trusted Block Explorer

The vaults.fyi API suite powers real-time, onchain analytics for DeFi yield opportunities and transactional capabilities across leading protocols.

In this case study, we explore how Etherscan—Ethereum’s go-to block explorer—leveraged both our Insights API and Earn API to enhance the user experience with the Etherscan Cards integration.

The Idea: Contextual Yield Insights for User Addresses

When users explore an Ethereum address on Etherscan, they’re often looking to understand what that wallet holds and how it’s being used. But what if they could also see what those idle assets could be doing?

That’s where the vaults.fyi Insights API and Earn API come in. By surfacing real-time DeFi yield opportunities and enabling user interaction with vaults, they provide helpful, actionable context directly within the Etherscan interface.

Etherscan Cards for vitalik.eth

How It Works

Here’s how the integration functions behind the scenes:

1. Balance Detection

When a user views an Ethereum wallet address on Etherscan, the Insights API checks for idle balances in:

• ETH

• Stablecoins: USDC, USDT, and DAI

2. Opportunity Matching

Etherscan queries the Insights API to identify the top DeFi yield opportunities that match those assets, filtered by clear and trusted criteria.

3. In-Interface Display

The Yield Opportunity card is shown in the Cards tab of the wallet page (for example: vitalik.eth), highlighting:

• Token type (ETH or stablecoin)

• Estimated 7-day APY

• Protocol offering the yield

4. User Action

Interested users can click the card to visit vaults.fyi, where they can explore more detailed analytics via the Insights API, and use the Earn API to:

• Supply or withdraw funds

• Manage DeFi positions

• Take direct onchain actions in a user-friendly interface

Search Criteria for Yield Opportunities

To ensure only higher quality, high confidence opportunities are shown, the following criteria are used:

• ETH Vaults: Must have a Total Value Locked (TVL) over $100 million. The vault with the highest 7-day APY is selected.

• Stablecoin Vaults: Same rules apply for USDC, USDT, and DAI—only vaults with >$100 million TVL are considered, and the top APY is surfaced.

This ensures that users are presented with yield options that are not just enticing, but also backed by substantial liquidity and protocol maturity.

The Bigger Picture: API-Powered UX

Etherscan’s Cards integration is just one example of what’s possible with the vaults.fyi Insights API and Earn API:

• The Insights API delivers real-time, structured data on user wallet balances and corresponding yield opportunities.

• The Earn API helps developers build frictionless DeFi interactions—allowing users to supply, withdraw, or manage funds directly within integrated apps or platforms.

Together, these APIs create a seamless, informed experience that empowers users to get more out of their onchain assets—right from the tools they already trust.

Build with vaults.fyi

Whether you’re building a wallet, dashboard, portfolio tracker, or DeFi application, vaults.fyi is your backend for yield discovery and execution.

With the Insights API and Earn API, you can:

✅ Deliver actionable yield insights ✅ Connect users to trusted opportunities ✅ Enable native onchain transactions from inside your product

Ready to integrate DeFi insights into your product? Chat with us.