Altcoin Season
Altcoin season is informal slang for a period when many altcoins outperform Bitcoin. There is no agreed threshold; some websites publish their own index.
Altcoin season is informal crypto slang for a stretch when many coins other than Bitcoin outperform Bitcoin. There is no official definition; data sites publish their own indexes with their own rules.
- Category
- Market Language and Slang
- Reading time
- 3 min
- Also called
- Altseason, Alt season
- Updated
Altcoin season in plain words
“Altcoin season” (or “altseason”) is a phase when altcoins as a group clearly beat Bitcoin's returns.1
One popular rule: if three-quarters of the top 100 coins have beaten Bitcoin over the past 90 days, it counts as altcoin season.2
Other sites use different coin lists and windows, so “altcoin season” is a label, not a fixed threshold.
How altcoin season indexes are built
Pick a coin list
CoinMarketCap uses the top 100 coins; other sites use a different count.
Remove look-alikes
Leave out stablecoins and wrapped or asset-backed tokens (for example WBTC or stETH), because they just mirror other assets.2
Measure returns
Compare each coin’s rolling 90-day return with Bitcoin’s.
Count the winners
Work out the share of coins that beat Bitcoin.
Label the reading
Read the score: 75% or more means altcoin season, while 25% or less means Bitcoin is leading.2
Check the risk
Size positions for big swings — crypto prices can drop fast and far.3
Worked examples
Example 1 — Reading an index
Altcoin seasonA hypothetical index shows 80 of the top 100 coins beat Bitcoin over 90 days.
| Share beating BTC | 80% |
| Threshold | 75% |
Under CoinMarketCap’s rule, 75% or more of the top 100 outperforming Bitcoin over 90 days counts as Altcoin Season.2
Example 2 — Falling dominance in a sell-off
False signalBitcoin’s market share drops from a hypothetical 55% to 50% while stablecoin balances grow.
| BTC dominance | 55% → 50% |
| Altcoin prices | Flat to lower |
Falling Bitcoin dominance is not proof of altseason: money fleeing into stablecoins in a scare lowers it too.1
Example 3 — Bitcoin season
Bitcoin seasonOnly 20 of 100 hypothetical coins beat Bitcoin over 90 days.
| Share beating BTC | 20% |
With a quarter or fewer of the coins beating Bitcoin, the index signals a Bitcoin-led market.2
Altcoin season vs Bitcoin season
| Aspect | Altcoin season | Bitcoin season |
|---|---|---|
| Who leads | Most altcoins | Bitcoin |
| Index reading | High (e.g. 75+) | Low (e.g. 25 or less) |
| Typical mood | Risk-seeking | More cautious |
| Main risk | Late-cycle reversals | Altcoins lagging |
Where the term is used
Market mood
A shorthand for Fear and Greed style sentiment in crypto.
Portfolio checks
Reviewing Portfolio Allocation between Bitcoin and other coins.
Relative strength
Comparing a Trading Pair such as an altcoin against BTC.
Risk control
Reminding traders that Volatility rises in speculative phases.
Advantages and disadvantages
Advantages
- Simple summary of a broad market move.
- Free indexes are easy to check.
- Puts altcoin returns in context against Bitcoin.
Disadvantages
- No agreed definition or threshold.
- Backward-looking: it describes the past 90 days.
- Different sites give different readings.
- Can encourage chasing late in a move.
Going deeper
Read as far as you need. Each level builds on the one before it.
It is a label, not a law
Beginner
Altseasons usually come with upbeat sentiment, which is exactly when the urge to chase is strongest.2
Context from Bitcoin
Intermediate
Altseasons seldom start while Bitcoin itself is rocketing, so watch Bitcoin's trend alongside the index.1
Dominance traps
Advanced
Because dominance includes stablecoins, a fearful rush into them can drag Bitcoin's share down and fake an altseason signal.1
Common mistakes
Treating the index as a forecast
It measures past returns.
Comparing different indexes
Coin lists and windows differ.
Ignoring stablecoin effects
Falling dominance is not always altcoin strength.
Going all-in on small coins
Size positions for high volatility.
Check your understanding
Test yourself before moving on. Each answer comes with an explanation.
Key points to remember
- Altcoin season is informal slang, not an official term.
- Indexes compare altcoin returns with Bitcoin over a set window.
- Thresholds and coin lists differ by site.
- The index looks backward, not forward.
- Crypto assets can be very volatile.
Frequently asked questions
Is there an official altcoin season?
Is Ethereum an altcoin?
Does altcoin season mean I should buy altcoins?
Further learning
- Market Capitalisation
How coin rankings are set.
- Stablecoin
Why stablecoins skew dominance.
- Volatility
Why altcoins swing more.
- Portfolio Allocation
Balancing BTC and altcoins.
Sources
This article is written in our own words. The sources below support the specific facts, rules and figures marked with a number in the text. Links open the original publisher’s page.
- CoinGecko. What Is Altcoin Dominance & How to Identify an Altseason (opens in a new tab) Checked .
- CoinMarketCap. Crypto Altcoin Season Index (opens in a new tab) Checked .
- U.S. SEC (Investor.gov). Crypto Asset-Related Investments (opens in a new tab) Checked .
Educational content, not financial advice. Examples use hypothetical prices and simplified costs; actual fees, margin rules and regulations vary by broker, market and country. We are not affiliated with any publisher linked above. Last reviewed . Report an error or request a source credit.