A crypto bubble is a period in which the prices of cryptocurrencies or blockchain tokens rise far above any value that can be supported by their use, cash flows or adoption, driven mainly by the expectation of selling to someone else at a higher price. Like earlier financial bubbles, crypto bubbles end in a sharp collapse that leaves late buyers with heavy losses and is followed by a long bear market.
The term is applied in two ways. Narrowly, it describes particular episodes, most often the initial coin offering boom of 2017–18 and the broad rally of 2020–21 that unwound in 2022. More broadly, some economists and central bankers have argued that crypto assets as a class are a bubble because they have no intrinsic value, a view that supporters reject. Comparisons are often drawn with historical manias such as the Dutch tulip craze of the 1630s and the South Sea Bubble of 1720.
Crypto bubble in plain terms
Imagine a town where a certain trading card suddenly becomes fashionable. People buy cards not to collect them but because yesterday's buyers made money. Prices double, then double again. New card series appear every week, and people buy those too because the old ones went up. At some point the supply of new buyers runs out, a few holders try to sell at once, and prices fall faster than they rose.
A crypto bubble follows the same pattern with digital tokens. Each wave begins with a real innovation, then turns into a race to buy whatever is rising, until the money stops coming in.
How bubbles form
Economists often describe bubbles using the stages set out by Hyman Minsky and popularised by Charles Kindleberger in Manias, Panics and Crashes (1978): a new opportunity or technology, a boom fed by easy credit, a euphoric phase, profit-taking by insiders and finally panic. Crypto episodes fit that outline closely. Contributing factors include:
- Easy money. Low interest rates and large central bank stimulus, especially in 2020–21, pushed investors towards speculative assets.
- Low barriers to issuance. Anyone can create a token in minutes on a smart contract platform, so supply of new assets expands to meet demand.
- Narrative and social media. Slogans such as "to the moon", fear of missing out (see FOMO) and celebrity endorsements spread quickly.
- Leverage. Crypto platforms offered high leverage through perpetual futures and lending products, which amplified both the rise and the fall.
- Weak disclosure. Many tokens were sold with only a marketing whitepaper and no audited financial information.
The 2017–18 ICO bubble
The first large crypto bubble centred on the initial coin offering (ICO), in which projects raised money by selling new tokens, usually for Ether (ETH). Thousands of ICOs raised billions of dollars in 2017, many for projects that never shipped a product. Bitcoin (BTC) rose from under $1,000 at the start of 2017 to nearly $20,000 in December, and the total value of the crypto market peaked in early January 2018. As money poured into new tokens, Bitcoin's share of total market value (its dominance) fell to its lowest level on record at the time.
In July 2017 the US Securities and Exchange Commission (SEC) published its report on The DAO, warning that tokens sold to investors could be securities. Enforcement actions against unregistered offerings followed. Through 2018 prices fell steeply: Bitcoin lost more than 80% of its value by December, and many ICO tokens became close to worthless.
The 2021–22 boom and bust
The second large episode was broader. Alongside a new Bitcoin all-time high (ATH) of about $69,000 in November 2021, the boom took in decentralized finance (DeFi), non-fungible tokens (NFTs), meme coins and high-yield lending platforms. The total crypto market value was widely reported to have passed $3 trillion in November 2021.
The unwinding was triggered by rising rates and then by a chain of failures. In May 2022 the Terra algorithmic stablecoin UST lost its dollar peg and its sister token LUNA collapsed. The crypto lender Celsius filed for bankruptcy in July 2022, and the exchange FTX collapsed in November 2022 amid allegations of misused customer funds. Bitcoin fell below $16,000, and many smaller tokens fell to an all-time low (ATL).
Debate and lessons
Whether crypto as a whole is a bubble remains contested. Critics, including the Bank for International Settlements in its 2018 annual report, have questioned whether decentralised cryptocurrencies can work as money at scale. Supporters point out that Bitcoin has recovered from every crash so far and has gained institutional channels such as US spot exchange-traded funds approved in 2024. Both sides agree that specific episodes involved speculation far beyond any measurable use.
The collapses exposed recurring risks: counterparty risk at centralised platforms, outright fraud such as Ponzi schemes and rug pulls, and price manipulation through pump-and-dump schemes. They also accelerated cryptocurrency regulation, including the European Union's MiCA regime.