It feels like déjà vu. Back in late 2017, Bitcoin was breaking records and altcoins went on an absolute tear – everyday investors were turning crypto into headlines, and even casual traders saw gains measured in thousands of percent
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. Fast-forward to May 2025: Bitcoin is once again trading near six-figure levels, and chatter about an “altcoin season” is buzzing on social media. But is history about to replay itself, or is this hype a false alarm? In this article we’ll walk through the technical charts and market psychology, compare the 2017–18 bull cycle with today’s signals, and highlight what to watch if you want to catch the next wave without getting burned.
2017’s Altcoin Mania: Lessons Learned
In 2017–2018, altcoins outperformed Bitcoin by miles. Ethereum shot from around $8 to $1,400, XRP from $0.006 to $3.50, and dozens of other alt tokens had 10x or 100x rallies
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. This “altseason” was driven by a mix of frenzied speculation and real innovation. Investors chased new blockchain projects and ICO tokens (fueled by fear of missing out), while mainstream media lit the fuse by covering every price jump
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. In short, capital flowed out of Bitcoin and into nearly every other coin – dropping Bitcoin’s dominance from ~86% to below 39% at its 2018 trough
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. However, the 2017-18 cycle also taught cautionary lessons. Many retail traders hung on far too long or went “all in” on a single token only to see a brutal collapse. As Binance Square notes, top takeaways were to take profits on spikes, manage risk, and diversify during these parabolic moves
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. Those who waited until the very top got caught when Bitcoin corrected and dragged everything down. This history reminds us: if an altseason is coming, it may run hard but can also reverse quickly.
Signs Pointing to a New Altseason
So what’s happening in 2025? First, consider the big-picture halving cycle. Historically, major altcoin rallies have kicked off roughly 180 days after Bitcoin’s halvings
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. After the July 2016 halving, altcoins went from a $13 billion market to $540 billion by early 2018 – a 4,050% surge
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. Similarly, after the May 2020 halving, the altcap shot from $90 billion to $1.7 trillion in less than a year (~+1,788%)
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. The most recent halving (April 2024) suggests late-2024 or early 2025 could be the sweet spot for alts to catch up. Traders know this pattern well: according to FXEmpire, every previous halving was followed by a delayed but massive altcoin rally
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. On the charts, a key metric is TOTAL2 – the total crypto market capitalization excluding Bitcoin. A clear uptrend is emerging here.
Chart: Total crypto market cap excluding Bitcoin (TOTAL2) on a weekly timeframe. Notice the ascending channel from late 2022, and the recent bounce from ~$0.95T to ~$1.26T (April–May 2025)
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. In fact, TOTAL2 has surged about +32% from its April 2025 low
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. That bounce off the long-term support trendline (and a rising RSI, not shown) is a classic “breakout retest” pattern. Analysts like @bitcoinwallah highlight that if this channel repeats, TOTAL2 could soon retest ~$1.8–2.0 trillion – a 40–60% upside
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. In plain terms, alts are quietly gaining market share. Meanwhile Bitcoin’s dominance (its share of total market cap) has been hovering near 60–64%. As of mid-May 2025, Bitcoin made up roughly 62–63% of crypto market value
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. It briefly spiked to ~64.4% in early May before dipping into the low 60s
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. (CoinMarketCap currently lists BTC dominance ~62.6%
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.) The flip side is that altcoins (collectively) are only about 30–38% of the market. Glassnode reports “altcoins” at ~22.3% (excluding ETH)
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, with Ethereum at ~9.8%
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. Even with a recent pullback in Bitcoin share, ETH and alts remain well below their 2017 peaks (18% and 28.5% respectively
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). In other words, Bitcoin is still king… but its throne is weakening slowly. Social and sentiment signals also matter. Google Trends for “crypto” and “altcoin” are still very low – retail has largely left the building. One analyst notes, “Search interest for crypto is near cycle lows”
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, meaning the general public isn’t frantically Googling crypto like in 2017. On the other hand, the Crypto Fear & Greed Index is firmly in “Greed” territory. CoinMarketCap’s own index shows ~66/100
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, Binance cites ~70
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, and alternative.me has it around 74 (as of mid-May)
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. That suggests crypto investors are optimistic (perhaps overly so), a sign that a crowd could be piling in – or already bought in. Combined, these clues paint a mixed picture: mainstream hype is muted, but dedicated traders are bullish. Key Indicators to Watch:
Alt market capitalization (ex-BTC): The TOTAL2 index is in an uptrend
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. A sustained break above the ~$1.3T level would confirm broad alt strength.
Bitcoin dominance: Many say a drop below ~58% dominance would mark a full-blown altseason
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. So far we’re above that; a decisive breakdown in BTC dominance would be a big red flag that “alt money” is rotating.
Altcoin Season Index: Bitget’s Altseason Index (for example) flips to “on” only when 75% of large alts outperform BTC over 90 days
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. Watching such metrics can tell you if this rally is really an altseason or just minor rotation.
Sentiment (F&G / Trends): Excessive greed (F&G in the 70s) warns of a crowded trade, while still-low Google Trends suggest we aren’t at full-blown mania yet
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. A spike in Google searches or social mentions for crypto could indicate FOMO kicking in – something that did happen in late 2017.
Parallels and Contrasts: 2017 vs. 2025
The cycles have notable similarities. As Cas Abbé points out, Q1 patterns look alike: altcoins were quiet early in 2017 and 2025 alike. In Q1 2025, altcoin market cap barely budged (+5.2%), while Bitcoin’s dominance rose ~12%
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. That mirrors early 2017 when Bitcoin led and alts lagged, right before the rotation. Even the broader backdrop has echoes of 2017 – in both cycles we have the same U.S. president (Donald Trump) and macro uncertainty, which some traders cheekily note as a “political parallel”
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. Yet there are differences too. In 2017, newcomers flooded in and news headlines raved about crypto in every major outlet
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. Today’s market has matured: institutions and regulations matter more. Some argue smart money is entering alts early – for example, analysts highlight growing institutional interest and the prospect of regulated altcoin ETFs as bullish signs
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. Emerging sectors (AI, real-world assets, DePIN) give investors new narratives beyond mere speculation. These could be catalysts that weren’t around in 2017. Conversely, the absence of retail frenzy and stricter scrutiny (SEC lawsuits, etc.) means today’s alt rally may be more measured.
What This Means for Traders
Every altseason is a rush, but smart participants temper greed with strategy. If 2025 really is ramping up, traders should watch out for breakouts and volume surges in the broad market rather than betting all on one token. Diversification and stop-losses are safer than chasing the latest meme coin (we saw how that ended for some in 2018). The story of 2017 reminds us: lock in gains when a coin rockets, and don’t fall victim to FOMO bubbles
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. It’s also wise to weigh fundamentals. Not all alts will repeat 2017’s meteoric runs – many projects today have stronger teams, products, and (in some cases) earnings models. Still, fast gains often come from hype cycles rather than fundamentals. As we watch charts like TOTAL2 and indicators like BTC dominance, remember that the market narrative matters. A true altseason typically unfolds after Bitcoin plateaus, making risk-on capital available for alts. Until we see that shift, it may pay to be patient or selective.
Outlook: A 2017 Replay – or Something New?
So, are we in an Altseason redux or just a modest bull market phase? The data suggest the early ingredients are there (halving +180d, rising alt market cap, creeping dip in BTC dominance, optimistic sentiment), but the final fuse hasn’t blown. If Bitcoin dominance decisively falls (below ~58–60%), or if charts break obvious resistance, then the “all aboard the alt-train” scenario gains credence
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. Until then, it might look and feel like mid-2017: a lot of buzz, but still early. We’d love to hear your take: do the current trends remind you of 2017’s launchpad, or is it different this time around? Are you loading up on ETH/ALT now, or waiting on the sidelines until the pattern is undeniable? Drop a comment below with what you’re seeing and where you think this story goes. One thing’s for sure – in crypto, history rarely repeats exactly, but it often rhymes. Stay curious, stay cautious, and enjoy the ride! Sources: Analysis references include Binance research and reports
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, CoinTelegraph market data
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, Tangem and Bitget market insights
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, and up-to-date metrics fr
om TradingView and Glassnode
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coinmarketcap.com
, among others.
