vaults.fyi is an API for onchain finance providing real-time market data, transaction payloads, and portfolio tracking for DeFi yield across 1,000+ vaults on 20+ networks. Used by Jumper, Kraken Wallet, Maple Finance, and Gauntlet.

What DeFi protocols does vaults.fyi support?

vaults.fyi supports 80+ protocols including Aave, Morpho, Compound, Euler, Lido, ether.fi, Sky, Yearn, Pendle, Kamino, and more, across Ethereum, Base, Arbitrum, Optimism, Solana, and 20+ networks.

How accurate are the APY rates on vaults.fyi?

All APY rates are calculated directly from onchain data, not scraped from protocol pages. Rates reflect what depositors actually earned, normalized across all protocols using standardized methodology.

How does the vaults.fyi transaction API work?

The transactions API generates ready-to-sign calldata for deposit, redeem, and claim actions. Transactions go directly to the protocol's own smart contracts with no intermediary and no custodian.

How do I get access to the vaults.fyi API?

Get an API key and make your first call in minutes at docs.vaults.fyi. The API covers standardized yield data, transaction payloads, and portfolio tracking across 1,000+ vaults on 20+ networks.

What is the best API for adding DeFi yield to a crypto wallet?

vaults.fyi is purpose-built for wallets integrating DeFi earn features. It provides market data to display rates, ready-to-sign transaction calldata for deposits and withdrawals, and portfolio tracking to show balances. Kraken Wallet and Jumper use it to power their earn and yield features across Ethereum, Base, Arbitrum, Solana, and 20+ networks.

How do fintechs integrate DeFi earn features into their apps?

The vaults.fyi API gives fintechs a single integration point for DeFi yield. The market data endpoints provide live APY rates across 80+ protocols. The transactions endpoints return ready-to-sign calldata so users interact directly with smart contracts. The portfolio endpoints track positions and earnings over time. There is no intermediary custody layer.

Does vaults.fyi work with AI agents and MCP?

Yes. vaults.fyi provides an MCP server that lets AI agents query live DeFi yield data, compare rates, and generate transactions directly within LLM workflows. Compatible with Claude, and any MCP-enabled AI agent framework.

What is yield-as-a-service?

Yield-as-a-service means embedding DeFi earning capabilities into any product through a single API, without building or maintaining protocol integrations yourself. vaults.fyi handles data normalization, onchain indexing, transaction construction, and portfolio tracking across 80+ protocols so your team can focus on product.

vaults.fyi: DeFi Yield API for Wallets, Apps & Fintechs

Why vaults.fyi

Build on data you can trust.

Every protocol exposes rates differently. Aave uses ray values (1e27), Compound uses per-block rates. Without standardization, cross-protocol data means writing a custom parser for every new integration.

Indexed from onchain state, not external APIs

Rates come directly from contract data. No reliance on protocol-provided endpoints that can go stale.

One schema across all 80+ protocols

APY is always a decimal. TVL is always in USD and native terms. No surprises when you add a new protocol.

Base, reward, and total yield broken out per vault

Every vault returns each yield component separately, using consistent methodology across every protocol and network.

GET /v2/detailed-vaults/base/0x0000...640D5

{
  "name": "Gauntlet USD Alpha",
  "address": "0x000000000001CdB5...640D5",
  "network": { "name": "base", "chainId": 8453 },
  "asset": { "symbol": "USDC", "assetGroup": "USD" },
  "apy": {
    "1day":  { "base": 0.0526, "total": 0.0526 },
    "7day":  { "base": 0.0485, "total": 0.0485 },
    "30day": { "base": 0.0462, "total": 0.0462 }
  },
  "tvl": { "usd": "67483050" },
  "remainingCapacity": "132505066859320",
  "transactionalProperties": {
    "depositStepsType": "complex",
    "redeemStepsType":  "complex"
  },
  "description": "Allocates across Morpho vaults in multiple stablecoins on mainnet and Base. Rewards auto-converted to USDC...",
  "score": { "vaultScore": 78.45 },
  "isTransactional": true
}

Same structure whether you query Gauntlet vaults, Morpho, Aave, or any of 80+ protocols.

API

Everything you need to build with yield.

Lido stETH

Supply ETH on Ethereum

2.53%

$19.83B

ether.fi eETH

Supply ETH on Ethereum

2.42%

$6.60B

Gauntlet USDC Prime

Supply USDC on Base

4.82%

$351.95M

Accurate APYs

Every rate is calculated from onchain data, not scraped from protocol pages. What you see is what depositors actually earned, normalized across all protocols.

8.1/10

Established

Protocol

Morpho

Network

Ethereum

Token USDC

Reputation Scores

Not all vaults are equal. Our scores factor in protocol track record, pool liquidity, and underlying asset risk, so you can weigh yield against risk.

Your active position

See historical deposit & withdrawal events, and track what you've earned on your position.

Position size

22,182.18 USDC

Total returns

+1,035.12 USDC

View position & activity ↗

Accurate P&L, no custom tables

Tracking real returns means logging every deposit and withdrawal across protocols, requiring teams to build custom tables from scratch. The portfolio API handles all of it: get precise returns by position, vault, and time range.

How transactions work

Direct to protocol.
No middleman.

Every transaction goes straight to the protocol's own smart contracts. Vaults.fyi prepares the calldata, your wallet signs it, and the protocol executes it directly.

No intermediary contracts. No custodian. Your funds are in the protocol, not ours.

Our yield integrations open monetization paths for your product. Earn alongside your users, without any additional infrastructure.

Read the transactions docs →

Transaction payload

GET /v2/transactions/deposit
  /0xd8dA...9604/mainnet/0x28B3...a43d

{
  "currentActionIndex": 0,
  "actions": [
    {
      "name": "Approve USDC for Spark vault",
      "tx": {
        "to": "0xA0b8...eB48", // USDC token contract
        "data": "0x095ea7b3...",
        "chainId": 1
      }
    },
    {
      "name": "Deposit USDC to Spark vault",
      "tx": {
        "to": "0x28B3...a43d", // Spark's contract
        "data": "0x9b8d6d38...",
        "chainId": 1
      }
    }
  ]
}

to: is always the protocol's own contract, never ours.

Testimonials

What builders and researchers say:

"Using a third-party data source signals to investors that Maple isn't grading its own homework."

Maple Finance

Maple Yield Performance 2024 report

"By using a third-party institutional-grade analytics provider like vaults.fyi, there's no opportunity to 'play games' with displayed APY data."

Cormac Daly

Founder, Nashpoint

"feels like @vaultsfyi has suddenly moved ahead of @DefiLlama for discovering yield opportunities."

crews.eth

@theyoungcrews

"@Vaultsfyi always has great data to track protocol growth!"

0xJibby

@0xJibby

"If you aren't using vaults for your onchain yield data, you are simply doing it wrong."

fatmac

@fat_mac2

"One of my new favorite sites for tracking onchain yield opportunities. Highly recommend."

Aes

@AesPoker

"Vaults.fyi is one of my most visited bookmarked sites. I use it daily to find the highest returning DeFi strategies."

Thomas Hepner

@thomas_hepner

"@vaultsfyi is a really really cool project."

fiddy

@fiddyresearch

Build the future of yield.

Get an API key and make your first call in minutes. Standardized yield data, transaction payloads, and portfolio tracking across 1,000+ vaults on 20+ networks.

For developers

Read the docs Get API key

Put your idle assets to work.

Connect your wallet and start earning from top DeFi protocols in under 60 seconds. No fees.

For savers going onchain

Open app

The API for onchain finance.