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Join us on DiscordA single 0–100 read on market sentiment, blended from multiple independent sources. Fear can signal opportunity; greed can signal risk.
The index compresses the emotional state of the crypto market into one number. It rises when traders are optimistic and buying aggressively (greed) and falls when they are anxious and selling (fear). It is most useful as a contrarian gauge: historically, extreme fear has clustered near local bottoms and extreme greed near local tops.
Because sentiment is noisy, Crypto Data API does not rely on one provider. We average several independent Fear & Greed readings into a single blended score, which smooths out the quirks of any individual methodology and gives a steadier signal.
The live value, classification and per-source breakdown are available from a single free endpoint:
curl -H "X-API-Key: cdk_live_yourkey" \ https://cryptodataapi.com/api/v1/sentiment/fear-greed
Add ?format=markdown for LLM-friendly plain-text output. For historical sentiment series, see /api/v1/market-intelligence/fear-greed-history.
A sentiment reading on its own is a talking point; a sentiment reading with the market state that produced it is a dataset. Every archived Fear & Greed print sits alongside the same day's market health score, breadth, derivatives positioning and macro backdrop, so you can test whether extreme readings actually marked anything.
curl -H "X-API-Key: cdk_live_yourkey" \ "https://cryptodataapi.com/api/v1/backtesting/snapshots?data_type=fear_greed&start=2026-05-09&limit=1000"