Stocks
A share is a unit of ownership in a company. When you buy one share of Apple you are, literally, a part-owner of Apple in that proportion. The price moves on what the market believes the company's future profits are worth. Shares trade on regulated exchanges with fixed hours.
By the TradingCalculator.Pro team · Updated on · About us
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Frequently asked questions
How is a company's market capitalization calculated?
Multiply the share price by the number of shares outstanding. A company trading at $50 with 1 billion shares has a $50 billion market cap. This is the correct way to compare the size of two companies — the share price alone tells you nothing.
What are the largest companies in the world by market cap?
The top of the table is persistently occupied by US technology companies — Apple, Microsoft, NVIDIA, Alphabet, Amazon, Meta — alongside Saudi Aramco. The exact order changes weekly; the live table on this page shows the current ranking.
What is a P/E ratio and what counts as high?
The price-to-earnings ratio is the share price divided by earnings per share. The S&P 500 historical average sits around 16-18. Above 25 the market is paying for strong expected growth; below 10 there is usually a problem — or an opportunity. It is only comparable between companies in the same sector.
What are US stock market hours?
9:30 to 16:00 New York time. Pre-market runs from 4:00 and after-hours until 20:00 ET, both with far less liquidity and much wider spreads.
What is free float and why does it matter?
It is the shares actually available to trade, excluding those locked up with founders, the state or insiders. With a small float a handful of orders move the price enormously — the feature shared by nearly every easily manipulated stock.