Altcoin Season Index

The Altcoin Season Index shows which phase the crypto market is in — “bitcoin season” or “altcoin season”. It measures how many of the leading altcoins outperformed bitcoin over the last 90 days and maps it to a simple 0–100 scale.

Altcoin season is a period when most altcoins rise faster than bitcoin and capital rotates out of BTC into riskier assets. The opposite phase is bitcoin season, when investors return to bitcoin as the crypto market’s “safe haven”. The Altcoin Season Index turns this tug-of-war into a single number so the phase is clear at a glance.

A value of 75 or above means altcoin season: most altcoins are rising faster than bitcoin. A value of 25 or below means bitcoin season: BTC is stronger than the alt market. The 26–74 range is a transition phase with no clear leader.

The index helps you quickly gauge market sentiment and see where capital is shifting — into bitcoin or into altcoins. That context is useful for portfolio management: alts, BTC and stablecoins behave differently across phases. The index does not replace your own analysis, but it saves time when reading the broader picture.

In practice, high readings (altcoin season) often coincide with overheated altcoins — some traders take profit then; low readings (bitcoin season) coincide with capital flowing from alts back into BTC. A transition phase signals uncertainty. Use the index together with technical analysis, dominance and risk management — not as a standalone signal.

The index is computed on TLAP’s own data from daily candles. For each altcoin in the tracked set we compute its 90-day return and compare it with BTC’s return over the same window; the index equals the share of alts that outperformed bitcoin. Data is recomputed every 3 hours.

Alongside the index we show bitcoin dominance (BTC.D), total stablecoin dominance and Ethereum dominance (ETH.D) — their shares of total market capitalisation. This helps you see where capital is flowing between bitcoin, stablecoins and altcoins.

Rising stablecoin dominance usually means investors are moving to cash and waiting — a “risk-off” mood. Falling stablecoin dominance often accompanies money flowing into bitcoin and altcoins. Ethereum dominance (ETH.D) is a proxy for the strength of the largest altcoin: its rise frequently precedes a broader alt rally.

Phase changes are driven by bitcoin cycles (including halvings), overall market liquidity, macro risk appetite, the growth of Ethereum and major altcoin ecosystems, and strong narratives — DeFi, L2s, AI tokens and others. Altcoin seasons have historically tended to follow a notable bitcoin rally, when capital seeks higher returns.

The index describes the current and recent state of the market — it does not predict the future. It is based on a 90-day window and a limited set of leading altcoins, so individual coins outside that set are not included. Sharp moves or changes in market composition can temporarily distort the picture — treat the value as a guide, not a precise forecast.

What does an index of 50 mean? It is the middle of the scale and a transition phase: roughly half of the tracked altcoins are outperforming bitcoin, with no clear leader.

How often is the Altcoin Season Index updated? The data is recalculated every 3 hours from TLAP daily candles.

Can the index predict an altcoin rally? No. The index reflects price action that has already happened over 90 days and serves as a guide to the current phase, not a forecast.

How many altcoins are included? The calculation uses a set of leading altcoins by market cap and liquidity; the set is periodically expanded as data becomes available.

This tool is for informational purposes only and is not investment advice.