You pull up a stock price at 11pm and it's sitting perfectly still. Refresh it, refresh it again -- same number. Is it broken, or is that actually the price? Understanding what a stock quote is showing you takes more than just reading the digits.
Markets have hours, and most trading happens in them
US exchanges like the NYSE and Nasdaq run their regular trading session from 9:30am to 4:00pm Eastern, Monday through Friday, excluding market holidays. That's when the bulk of buying and selling happens and when a stock's price is actively being set by new trades.
Outside that window, the exchange isn't matching new orders the same way. So a quote you check at night isn't stale in the sense of being wrong -- it's showing you the last actual trade price from when the market was open, because that genuinely is the most recent price that exists.
Pre-market and after-hours trading exist, but thinly
Some trading does happen outside regular hours, typically referred to as pre-market (before 9:30am ET) and after-hours (after 4:00pm ET). A stock's price can move in these sessions, often in reaction to news or earnings announced outside normal hours.
The catch is volume is much lower than during the regular session -- fewer participants means trades can swing the price more on relatively small orders. A big after-hours move doesn't always hold once regular trading resumes and more participants are active again.
Why "real-time" isn't automatically what you're seeing
Exchange data has historically had two tiers: real-time data, and delayed data (commonly delayed by around 15 minutes). Real-time consolidated market data has traditionally required a paid license, which is why a lot of free financial websites and apps show delayed quotes by default rather than the literal current trade. This isn't unique to any one site -- it's a structural feature of how market data licensing has worked for decades, and it's worth keeping in mind whenever you're looking at a free quote anywhere online.
For casual purposes -- checking roughly where a stock sits, watching a general trend -- a short delay rarely matters. For anything where the exact current price matters down to the second, like placing a trade, the price used is whatever your broker's order execution system provides at that moment, not a number read off a webpage.
What actually moves the number you're looking at
Every trade that executes on an exchange has a price, and the "current price" you see is simply the price of the most recent trade that's been reported to whatever data feed the site you're using pulls from. There's no separate formula behind it -- it's a running record of the last executed trade, updated as new trades happen during market hours.
That's also why the price can jump between two numbers that seem far apart if trading has been thin: it's not interpolating a smooth line, it's reporting exactly what the last trade printed at.
Checking a price without opening a brokerage app
If you just want to glance at where a stock is sitting -- day's range, how it compares to its 52-week range, recent volume -- you don't need a trading account for that. The Stock Price Tracker looks up any stock's current price along with its day range, 52-week range, and volume, no login required.