Prev Close
Previous Close
💡 What is Prev Close? - Today's Starting Line
Prev Close is short for Previous Close. In simple terms, it means the final trading price when the market closed the day before. Think of it like the "starting line" for today's race. The previous day's closing price is the reference point for judging whether a stock went up or down today. If the current price is higher than the previous close, the stock is "up"; if it's lower, the stock is "down."
Korean & English Key Terms
Previous Close | Closing Price | Opening Price | Gap Up | Gap Down | After-Hours Trading | Pre-Market | Regular Session | Settlement Price | Daily Change
The previous close may look simple, but it plays a very important role in the stock market. The regular trading hours of the U.S. stock market are from 9:30 AM to 4:00 PM Eastern Time, and the last trading price at 4:00 PM becomes that day's Closing Price. This closing price then becomes the "Prev Close" for the next trading day.
For example, if Apple (AAPL) closed yesterday at $175.50 and today's current price is $178.20, then the previous close is $175.50 and today's change is +$2.70 (+1.54%). The "+1.54%" number you see in a brokerage app or chart is the percentage change compared to the previous close.
🔍 Why Should You Look at the Previous Close?
The Basis for Calculating Daily Returns
To figure out whether a stock went up or down today, and by how much, you absolutely need the previous close. The daily change rate is calculated as: (Current Price − Previous Close) / Previous Close × 100. Every investment platform shows this number by default, and it's one of the first things investors check.
The Foundation of Gap Analysis
The difference between today's Opening Price and the previous close is called the "Gap." If the opening price is higher than the previous close, it's a Gap Up; if it's lower, it's a Gap Down. Gaps reflect news that came out between the market close and the next market open (earnings reports, economic data, global events, etc.). If Nvidia (NVDA) reports earnings after the close, the next day's opening price can start with a big gap of 10% or more above or below the previous close.
Basic Data for Technical Analysis
Almost all technical indicators—such as moving averages, Bollinger Bands, and RSI—are calculated based on the Closing Price. So the previous close is the fundamental data for technical analysis. The body of a candlestick shown on a chart represents the range between the opening and closing prices: if the close is higher than the open, it's a bullish (up) candle; if it's lower, it's a bearish (down) candle.
🔎 How to Check It
Brokerage Apps / Websites
All brokerage apps and financial websites display the previous close by default. It's usually shown on the stock's detail page alongside the current price and change rate, labeled as "Prev Close" or "Previous Close." You can also check the previous close in the overseas stock sections of Korean brokerages like Kiwoom Securities or Mirae Asset.
Finviz, Yahoo Finance, and Others
You can check the Prev Close directly on Finviz's stock detail page. On Yahoo Finance, it appears at the top of the stock page labeled "Previous Close." You can also search "AAPL stock" on Google to see the previous close right away.
Caution: Difference Between After-Hours Prices and the Close
In the U.S. stock market, trading is also possible outside regular hours—during Pre-Market (4:00–9:30 AM) and After-Hours (4:00–8:00 PM). After-hours prices can differ from the close, but the official "Prev Close" is the last price of the regular session (4:00 PM). Even if a stock moves sharply after an earnings release during after-hours, the Prev Close itself remains the price at the end of regular trading.
💡 How to Use It
Gap Trading Strategy
This is a trading strategy that uses the gap between the previous close and today's opening price. The "Gap Fill" strategy bets that the price will return to the previous close after a gap up. Statistically, small gaps (1–3%) are often filled during the trading day (price returns to the previous close). On the other hand, large gaps (5% or more) often don't fill and instead form a trend. When Tesla (TSLA) gaps up 10% after an earnings report, that gap is unlikely to fill.
Using It as Support/Resistance
The previous close acts as a psychologically important price level. Many investors judge whether they're in profit or loss based on the previous close, so it's common to see the stock find support or run into resistance near that level. Especially early in the trading day, the direction is often determined around the previous close.
A Reference for Placing Orders
When setting limit orders or stop-loss orders, the previous close is often used as a reference. For example, you can set rules like "sell if the price drops 3% below the previous close" or "sell if the price rises 2% above the previous close." This is especially useful for Korean investors who can't monitor the U.S. market in real time during the night—scheduled orders based on the previous close can come in handy.
🔗 Related Indicators
Open / Opening Price
This is the first trading price when the market opens today. The difference between the opening price and the previous close is the gap. If the opening price is higher than the previous close, it means buying pressure is strong from the start; if it's lower, there's selling pressure.
High / Low
These are the highest and lowest prices during the trading day. By looking at the high and low relative to the previous close, you can understand the day's volatility. If both the high and low are above the previous close, it was a very strong day; if both are below, it was a very weak day.
Change / Change %
Subtract the previous close from the current price to get the Change; divide that by the previous close and multiply by 100 to get the Change %. The numbers shown in green (positive) or red (negative) in stock apps are exactly this. In the U.S., green means up and red means down.
🎯 Practical Use
Planning Strategy Before the Market Opens
In the evening Korean time, before the U.S. market opens, check the previous close of stocks you hold and compare it with the pre-market price to predict today's market direction. If the pre-market price is significantly higher than the previous close, the market will likely open with a gap up; if it's lower, it'll open with a gap down. Based on this, you can set your buy/sell/wait strategy in advance.
Real-Time Profit/Loss Tracking
Most investment apps show the daily profit/loss of your holdings based on the previous close. You can see in real time how much you've made or lost today, and use this to decide whether to buy more, take partial profits, or cut your losses.
⚠️ Precautions
1. Don't confuse it with after-hours prices: Prices traded during after-hours or pre-market can differ from the regular close. The official Prev Close is the closing price of the regular session (4:00 PM ET).
2. Watch out for ex-dividend dates: On the day after the ex-dividend date, the stock price automatically drops by the amount of the dividend. The previous close for that day is the price before dividend adjustment, so it's normal for the price to fall by the dividend amount. High-dividend stocks like Coca-Cola (KO) typically drop 0.5–1% on their ex-dividend date.
3. Adjustment for stock splits: When a stock split occurs, the previous close is adjusted to reflect the split ratio. For example, if the closing price before a 2:1 split was $400, the Prev Close after the split will be adjusted to $200.
4. Check regular trading hours: The regular trading hours for U.S. stocks in Korean time are from 11:30 PM to 6:00 AM (10:30 PM to 5:00 AM during daylight saving time). The closing price is finalized around 5–6 AM Korean time.
5. Watch out for holidays: The market is closed on U.S. holidays (Independence Day, Thanksgiving, Christmas, etc.). In that case, the Prev Close refers to the closing price of the last trading day before the holiday. Be sure to check the U.S. holiday schedule in advance.
✅ Checklist
☑ Have you accurately checked the previous close? (Regular close, not after-hours price)
☑ Have you checked the gap between today's open and the previous close?
☑ Have you calculated the change rate (%) compared to the previous close?
☑ Have you checked for special situations such as ex-dividend dates or stock splits?
☑ Have you checked for significant pre-market/after-hours moves compared to the previous close?
☑ Have you checked whether the previous close is close to any major support/resistance levels?
☑ Have you built today's trading strategy based on the previous close?
☑ Have you appropriately set your stop-loss/take-profit orders based on the previous close?
❓ Frequently Asked Questions (FAQ)
Q. Why is there a big difference between the previous close and today's opening price?
A. The main reason is news released after the market closed. If an earnings report comes out during after-hours, the stock moves significantly in after-hours trading, and the next day's opening price differs greatly from the previous close. Other causes of gaps include trends in overseas markets (Europe, Asia), overnight economic data releases, and global political/economic events. Stocks like Nvidia (NVDA) or Tesla (TSLA) often see gaps of 5–15% after earnings releases.
Q. If a stock moves a lot in after-hours trading, does the previous close change?
A. No, it doesn't. The previous close (Prev Close) is fixed as the last price of the regular trading session. No matter how much the price moves in after-hours, the already-finalized closing price doesn't change. However, the next day's opening price can differ greatly from the previous close due to after-hours trading influence. This is the gap. After-hours prices are reflected in real-time quotes but aren't included in the official closing price record.
Q. When is the previous close finalized in Korean time?
A. Since the regular U.S. market closes at 4:00 PM Eastern Time (ET), the closing price is finalized at 5:00 AM Korean time during daylight saving time, or 6:00 AM Korean time during standard time. So the price Korean investors check in the morning is already the finalized previous close. U.S. daylight saving time usually runs from the second Sunday of March to the first Sunday of November.
Q. Is Friday's close the same as Monday's Prev Close?
A. Yes, since there is no trading over the weekend (Saturday and Sunday), Monday's previous close is the same as Friday's close. However, if news happens over the weekend (geopolitical events, corporate announcements, natural disasters, etc.), Monday's opening price can differ greatly from Friday's close. This is called the "Monday gap" or weekend risk. If Monday is a U.S. holiday and the market is closed, then Tuesday's Prev Close will be Friday's close.
🇰🇷 Notes for Korean Investors
How to use the time zones: For Korean investors, the previous close is "last night's result that you check in the morning." You can build a routine of checking the previous close in the morning, reviewing pre-market trends in the afternoon, and participating in the regular session at night. Checking for significant moves relative to the previous close during pre-market (6:00–10:30 PM or 7:00–11:30 PM Korean time) can help you prepare your trades.
Display in Korean brokerages: Korean brokerage apps often show the previous close of U.S. stocks in both USD and KRW-converted amounts. The KRW-converted amount uses that day's exchange rate, so your return in KRW can differ from your return in USD due to exchange rate movements.
Using scheduled orders: Scheduled orders based on the previous close are essential for Korean investors who can't watch the market all night. By setting conditional orders in advance—such as "buy if the price drops 3% or more below the previous close" or "sell if the price rises 5% or more above the previous close"—you can execute trades at your desired prices even while you sleep.
Key time zones to remember: 4:00 PM ET (closing price finalized) = 5:00 AM Korean time (daylight saving) / 6:00 AM Korean time (standard). 9:30 AM ET (market open) = 10:30 PM Korean time (daylight saving) / 11:30 PM Korean time (standard). Keep these times in mind.