Updated July 29, 2026
If your feed is suddenly full of “Kospi crash” headlines, here’s the plain-language version: what actually happened over the past two sessions, why SK Hynix’s earnings report made things worse instead of better, and what’s fueling the panic beyond one company’s numbers.
What’s happening with the Kospi right now?
The Kospi fell nearly 11% on Tuesday and extended losses by over 8% Wednesday, triggering trading halts on both days and taking its two-day slide past 16%.
Tuesday’s close at 6,023.63 marked the index’s worst single-day performance in almost five months. Wednesday’s session picked up right where Tuesday left off, with the Kospi sliding to around 5,283 points, its lowest level since early April, before a 20-minute circuit breaker halted trading market-wide. The tech-heavy Kosdaq fell alongside it, dropping more than 7% on Tuesday.
| Session | Kospi Move | What Triggered |
|---|---|---|
| Tuesday, July 28 | Fell nearly 11%, closed at 6,023.63 | Sell-side “sidecar” mechanism activated |
| Wednesday, July 29 | Fell over 8% intraday to ~5,283 | Level 1 circuit breaker, 20-minute halt |
| Two-day total | Down more than 16% | — |
Why did SK Hynix’s earnings make the selloff worse?
SK Hynix posted record profit but missed analyst forecasts, and its shares plunged as much as 20% because of how much weight it carries in the index.
SK Hynix reported revenue up 257% and operating profit up 557% from a year earlier, both records. But the numbers still came in below what analysts expected, and that was enough to send shares tumbling below the company’s US IPO offer price. Because SK Hynix and Samsung Electronics together make up an outsized share of the Kospi’s total value, weakness in just those two names is enough to drag the whole index down, even when other sectors are holding steady.
What else is spooking investors beyond one earnings miss?
Three things are converging: fears about the size of AI infrastructure spending, China’s fast-growing chip competitor CXMT, and reports of progress in Chinese chipmaking equipment.
Reports that Nvidia is considering backing as much as $250 billion in financing for an OpenAI-led data center project, while OpenAI separately weighs buying hundreds of billions of dollars in Nvidia chips, have raised “circular financing” concerns about whether AI spending numbers are as solid as they look. At the same time, China’s ChangXin Memory Technologies closed its Shanghai market debut more than 460% above its offer price, the largest A-share IPO since 2010, reviving worries about how fast Chinese memory capacity could scale. Reports that China has also made progress on domestic chipmaking equipment added to the unease.
Reasons For Calm
- The Kospi remains well above year-earlier levels despite the rout, after a strong AI-fueled rally earlier in 2026
- The won has stayed fairly stable, suggesting concentrated equity selling rather than a broader flight from Korean assets
- Retail investors bought over ₩2.2 trillion of shares during the selloff, a sign some see this as a buying opportunity
Reasons For Caution
- The rally that got the Kospi here leaned almost entirely on two stocks, Samsung and SK Hynix, leaving it fragile to swings in just one sector
- July is on pace to be the Kospi’s worst monthly performance on record, with losses exceeding 30% for the month
- China’s DRAM competitor is expanding right at the peak of the current memory cycle, not a quiet moment
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Browse Business and FinanceHow does this compare to past Kospi selloffs?
Wednesday’s halt was the Kospi’s 8th circuit breaker of 2026, part of a pattern of instability in a market that’s become heavily concentrated in semiconductor stocks.
South Korea’s index-wide circuit breaker exists specifically to slow down panic selling, pausing trading for 20 minutes once losses pass 8% in a single session. Triggering it on back-to-back days is rare, and underscores just how much the Kospi’s fortunes now ride on a handful of chip names. The same concentration that powered the index to huge gains during the AI rally is now working in reverse.
This isn’t investment advice
Circuit-breaker days are exactly the kind of moment that tempts people into panic selling or panic buying. If you hold Korean tech stocks or funds tracking the Kospi, treat any single day’s headlines as one data point among many, not a signal to act immediately. A licensed financial advisor can help you think through what a concentrated, volatile market like this means for your specific situation.
What should investors watch next?
Samsung Electronics reports earnings Thursday, followed by the US Federal Reserve’s policy decision and results from Microsoft, Meta, Amazon, and Apple this week.
Those events will give the market a clearer read on whether AI infrastructure spending is genuinely slowing or whether this is a case of extremely high expectations meeting normal earnings noise. Until then, expect volatility to stay elevated across Korean, Japanese, and Taiwanese chip stocks, which have all moved in tandem with the Kospi this week.
Frequently Asked Questions
How much has the Kospi fallen this week?
The Kospi fell nearly 11% on Tuesday and extended losses by more than 8% intraday on Wednesday, bringing its two-day decline to more than 16%.
Why did SK Hynix’s stock drop despite record profit?
SK Hynix’s earnings, while a record, still missed analyst forecasts, and because the company carries heavy weight in the Kospi, its double-digit share price drop pulled the whole index down.
Is China’s CXMT really a threat to Samsung and SK Hynix?
CXMT is growing fast in conventional DRAM and its blockbuster stock debut rattled sentiment, but it hasn’t yet challenged Korea’s lead in the specialized HBM chips used in AI accelerators.
What triggers a Kospi circuit breaker?
A market-wide circuit breaker halts trading for 20 minutes once the index falls more than 8% in a single session, a mechanism designed to slow down panic selling.
Bottom Line
This week’s Kospi selloff is really a story about concentration: a market that rode two chip stocks to huge gains is now feeling what happens when those same stocks wobble. The underlying AI demand picture hasn’t collapsed, at least not according to the export and revenue data so far, but expectations had climbed so high that even record earnings weren’t enough to satisfy them. Samsung’s earnings and the Fed’s decision later this week should offer the next real test of whether the selling has run its course.
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Explore More Finance ArticlesSources: Investing.com, TradingKey, EBC Financial Group, Trading Economics, NAI 500, BigGo Finance.