Stock Split Calculator
Calculate post-split shares, new share price, and adjusted cost basis. Works for forward and reverse splits.
| Company | Year | Ratio | Type | Notes |
|---|---|---|---|---|
| Apple (AAPL) | 2020 | 4-for-1 | Forward | 4th split in Apple's history |
| Tesla (TSLA) | 2020 | 5-for-1 | Forward | First split since IPO |
| Amazon (AMZN) | 2022 | 20-for-1 | Forward | First split since 1999 |
| Alphabet (GOOGL) | 2022 | 20-for-1 | Forward | Made shares more accessible |
| Nvidia (NVDA) | 2024 | 10-for-1 | Forward | Post AI rally, price was ~$1,200 |
Why Companies Split Their Stock
A forward stock split increases share count and reduces price proportionally, leaving total market value unchanged. Companies typically split when the share price has risen to a level that might seem expensive or inaccessible to smaller investors. A $1,000 stock that splits 10-for-1 becomes a $100 stock — same company value, lower per-share price.
Why Total Value Does Not Change
Think of a pizza: cutting it into more slices does not create more pizza. A 2-for-1 split gives you twice as many shares at half the price. Your investment is worth exactly the same dollar amount on the day of the split. Post-split price movements are what create or destroy value.
Reverse Splits
A reverse split reduces share count and increases price by the same ratio. The most common reason is to avoid delisting — major exchanges like the NYSE and Nasdaq require stocks to maintain a minimum price (typically $1). A stock at $0.50 might do a 1-for-10 reverse split to bring the price to $5. Reverse splits are often a red flag, indicating the company has struggled enough that its price fell to a dangerously low level. However, not all reverse splits are distress signals — some are done as part of corporate restructuring.
Options Contracts After a Split
When a stock splits, options contracts are automatically adjusted. In a 2-for-1 split, each options contract (normally 100 shares) becomes a contract for 200 shares at half the strike price — maintaining the same total economic value. Your broker and the Options Clearing Corporation handle this adjustment automatically.