Bitcoin fell 10% as losses swept the largest cryptoassets

Bitcoin and other large cryptoassets fell together on January 21, 2018, reversing part of the weekend rebound that had followed the previous week’s rout. Kraken’s daily market report put bitcoin at $11,445, down 10.7% over the report’s daily window, with $191 million traded in bitcoin markets on the exchange. Kraken reported $583 million of trading across all of its markets.

The weakness was not confined to bitcoin. In the same Kraken report, ether was $1,042.40, down 9.85%; XRP was $1.3489, down 14.6%; and bitcoin cash was $1,751.56, down 15.6%. Every non-stable cryptoasset listed in Kraken’s summary was negative, while USDT was shown unchanged at $1.01. That breadth made the session more consequential than an isolated move in one token: the selling reached payment assets, smart-contract platforms and privacy-focused coins at once.

A second dataset confirms the breadth

CoinMarketCap’s historical snapshot for January 21 recorded bitcoin at $11,600.13, down 9.62% over 24 hours, with a reported market capitalization of $195.09 billion and $9.94 billion in aggregated 24-hour volume. Ether was $1,049.58, down 8.66%, and XRP was $1.38, down 11.97%.

All ten assets at the top of CoinMarketCap’s ranking were lower over 24 hours. Their declines ranged from ether’s 8.66% to cardano’s 12.67%. Bitcoin cash lost 11.71%, litecoin 9.25%, NEM 11.07%, NEO 11.50%, EOS 11.83% and stellar 12.46%. The uniform direction across the ranking is the clearest verified fact of the day.

The two datasets do not give identical bitcoin prices or percentage changes. That is expected because Kraken described activity on its own venue, while CoinMarketCap aggregated market information and captured a historical snapshot. Their cutoff times, eligible trading pairs and pricing methods were not stated on the surviving pages. The figures should therefore be read as separate measurements that corroborate direction and magnitude, not as interchangeable closing prices.

What the selloff showed

The January 21 move mattered because crypto trading did not pause for the weekend. A sharp January 21 decline could reset prices before traditional financial markets reopened, while participants faced thinner or differently distributed liquidity than during weekday hours. That liquidity explanation is an interpretation, not something the surviving reports directly measure.

The breadth also complicates single-cause explanations. Regulatory anxiety in several jurisdictions was part of the contemporaneous backdrop, but the cited market records do not establish that regulation—or any one headline—caused the decline. What can be said with confidence is narrower: sellers marked down nearly every major liquid cryptoasset in the two observed datasets, and bitcoin remained far below its December 2017 peak.

For institutions considering custody, derivatives or exchange exposure, the episode reinforced the operational importance of venue selection and time conventions. A “daily” crypto return depended on the chosen exchange and cutoff even when the market signal was unmistakable.

Later clarification

A CoinDesk report published on January 22, 2018, said bitcoin had approached $13,000 during January 20 trading before falling below $12,000 on January 21. That later account helps establish the sequence around January 21, but it is not used here to import January 22’s further decline toward $10,000 into the event-day record.