Intraday Trading (Jangjung)
Overview
Intraday trading (Jangjung, 場中) refers to the state during which regular trading hours are in progress in the stock market. Generally, the regular trading hours for the KOSPI and KOSDAQ markets of the Korea Exchange are from 9:00 AM to 3:30 PM, and all trading and price movements occurring during this time are called 'Jangjung.' Intraday trading is the most important period when investors buy and sell stocks in real time and prices are formed, characterized by the highest market liquidity and volatility.
Main Content
Time Segments of Intraday Trading
Intraday trading is broadly divided into three segments. First, the morning session (9:00 AM–12:00 PM) reflects the previous day's overseas market trends, corporate earnings announced before the market opens, and economic indicators, and tends to have high volatility. Second, the afternoon session (1:00 PM–3:20 PM) often continues or reverses the morning trend, and is a time when large-scale trading by institutions and foreign investors is concentrated. Third, the closing call auction period (3:20 PM–3:30 PM) is the 10 minutes before the market close, switching to single-price trading to determine the final execution price. During this time, sharp price fluctuations can occur, requiring caution.
Key Intraday Indicators
Key indicators that intraday investors pay attention to include trading volume, trading value, number of advancing and declining stocks, program trading trends, and supply-demand trading trends (by individuals, foreigners, and institutions). In particular, trading volume and trading value indicate market activity, while program trading—large-scale orders for arbitrage or hedging linked to futures and options—becomes a factor that amplifies intraday volatility.
Intraday Strategies
Intraday trading is divided into short-term trading (day trading) and swing trading. Day traders profit from short-term price movements during the session, while swing traders capture intraday trends over a holding period of several days to weeks. Major strategies include chart analysis (moving averages, Bollinger Bands, MACD, etc.), news trading (earnings announcements, policy releases, etc.), and supply-demand analysis (tracking net buying by foreigners and institutions). In particular, the volatility breakout strategy is frequently used during intraday trading, which involves trading when the price breaks through a certain range compared to the previous day.
Intraday Risk Management
Intraday trading carries a high risk of loss due to rapid price fluctuations. Therefore, setting a stop-loss is essential, and extra caution is needed when using leverage (credit trading, futures). Additionally, the market can change abruptly during the session due to disclosures or sudden news (e.g., geopolitical risks, interest rate hike announcements), so it is important to monitor news and appropriately adjust position sizes.
Recent Trends
As of 2024–2025, the intraday trading environment is undergoing significant changes. First, the spread of AI-based algorithmic trading has increased ultra-short-term trading during the session. As artificial intelligence analyzes real-time news, social media sentiment, and chart patterns to make trading decisions in milliseconds, it has become more difficult for individual investors to respond. Second, individual investors' participation rate during intraday trading has increased. Since the 'Donghak Ant Movement' centered on the MZ generation, there have been many days when the individual investor share exceeds 60%, and they tend to actively trade mainly in the early part of the session. Third, expanded intraday volatility is prominent. Due to global economic uncertainties (high interest rates, inflation, geopolitical conflicts), intraday price ranges have widened compared to the past, and sharp intraday fluctuations are frequent, especially on days when the U.S. Federal Reserve (Fed) announces interest rate decisions or key economic indicators are released. Fourth, discussions on resuming intraday short selling continue. Short selling, banned after COVID-19 in 2020, was partially resumed in 2024, which has somewhat increased downward pressure during the session. However, institutional safeguards to protect individual investors (e.g., designating short-selling overheated stocks) have also been introduced. Fifth, the importance of intraday news flashes has grown further. As AI news analysis services (e.g., sentiment analysis) become common, the phenomenon of corporate earnings, government policies, and international affairs news announced during the session being immediately reflected in stock prices has intensified.
Related Topics
- [[Stock Market]]
- [[Day Trading]]
- [[Volatility]]
- [[Short Selling]]
- [[Algorithmic Trading]]
---
AI-generated document · Improved by the community