BlockShield/Metrics/Altcoin Season Index

Altcoin Season Index

A 0-100 read on whether alts are outperforming Bitcoin, with stablecoins, wrapped and asset-backed tokens excluded because they track something else.

Drawn on the Market Regime tabAPI /api/v1/market/regimethe in-house price universe (top-coin performance)Binance daily klines

What it measures

How broadly the market's larger alternatives are outperforming Bitcoin over the measurement window, expressed 0-100. High readings describe an altcoin season; low readings describe a Bitcoin-led market.

It is a breadth measure. It says how many coins beat Bitcoin, not by how much, which is why it can be high in a market where the total capitalisation barely moved.

How it is built

The index is computed over the platform's own cached coin universe, so it shares a snapshot with every other surface that reads that universe and cannot disagree with them the way two separately cached snapshots once did.

Stablecoins are excluded, and so are wrapped, liquid-staking and asset-backed tokens. A token that tracks another asset — a wrapped Bitcoin, a staked Ether, a tokenized gold or treasury — is not an 'alt', and including it measures the asset it tracks.

The exclusion list is enumerated explicitly rather than pattern-matched on names, because name shapes collide with real assets.

It ships from the same engine as the Market Regime score, so the breadth dimension the composite uses and the index shown beside it are the same computation.

What to watch

A breadth index near an extreme is a description of the last window, not a prediction about the next one.

Membership choices move this number. A universe that admits more small caps produces more coins capable of beating Bitcoin over any short window.

Read it with the narrative baskets: breadth says how many won, the baskets say which story capital actually paid for.

Open the live Market Regime tab →

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Every rule above is enforced in code and pinned by a test. The doctrine they all follow — NULL is not zero, partial cannot erase, an unfinished period is not evidence — is published on the methodology page.
Descriptive, not advice. Every score, band and verdict on this platform is an automated heuristic over public data and can be wrong in both directions. All metrics · Methodology · About · Dashboard