▓▒░ FUNDAMENTAL

API

Programmatic access to the same yield data the site renders. Single-header auth, plain JSON, free and paid tiers. Base URL https://api.fundamental.fi.

Plans

Two tiers. Free gives you a realised APY for every venue; paid unlocks the depth: the full per-token, per-method history, with multiple capture methods per venue for cross-validation.

Free$0
/api/yields
  • Every tracked venue
  • One realised USDC APY each
  • Most faithful capture method
  • Daily refresh at 02:30 UTC
Paid$5/mo · $50/yr
/api/yields-v3
  • All venues, all tokens
  • Every capture method
  • Full history
  • Cross-validation across methods

Get a key

Authenticate with a Solana wallet, then sign a message to prove ownership. Paid registrations require a single USDC transfer to Fundamental's treasury before activation.

Connect a Solana wallet to create or retrieve your key.

Endpoints

GET/api/yieldsFree

One realised APY per venue. Values are decimals (0.05 means 5%). Bound the series with ?period=7d|30d|90d|1y.

Request
curl "https://api.fundamental.fi/api/yields?period=30d" \
  -H "X-API-Key: YOUR_KEY"
/api/yields-v3

Per-token, per-capture-method yields, keyed source → token → capture method, so a single protocol can expose multiple series for cross-validation.

Response · 200
{
  "kamino": {
    "USDC": {
      "sdk":        [{ "date": "2025-12-01", "apy": 0.0534 }, ...],
      "share_math": [{ "date": "2025-12-01", "apy": 0.0530 }, ...]
    }
  },
  "jupiter": { "USDC": { "api": [...] } }
}

Authentication

Send your key as a header on every request:

HTTP
X-API-Key: your_api_key_here
401
Missing or invalid API key.
403
Key expired, or the endpoint requires the paid plan.