Stock split calculator

This adjusts share count, price, and per-share cost basis for a forward or reverse split. The position's market value and total cost stay the same. A split does not, by itself, change what the holding is worth. The stock split guide uses the same example.

New shares = old shares × (shares received ÷ shares exchanged). New price = old price × (shares exchanged ÷ shares received).

Shares after the split

Enter the position and the split ratio.

How to adjust a position for a split

Enter shares, price, and cost per share. Cost per share is the basis you track for the lot, before the split.
Enter the split as shares received and shares exchanged. A 4-for-1 split is 4 received and 1 exchanged. A 1-for-10 reverse split is 1 received and 10 exchanged.
Check that the totals match. Share count and per-share figures change. Market value and total cost basis do not.

Frequently asked questions

How does a stock split change shares and price?: Multiply the share count by the shares you receive and divide by the shares you exchange. Divide the price and the per-share cost basis by that same factor. A 4-for-1 split turns 100 shares at $200 into 400 shares at $50. A $150 cost basis becomes $37.50 a share. The position is still worth $20,000, and the total cost is still $15,000.
What do you enter for a reverse split?: Enter fewer shares received than shares exchanged. A 1-for-10 reverse split is 1 received and 10 exchanged. The share count falls and the price rises. The total value and the total cost stay the same.
Is this investment advice?: No. The calculator is for general informational and educational purposes only. A split does not, by itself, change what the position is worth.

Related guides

How to adjust a position for a split

Enter shares, price, and cost per share. Cost per share is the basis you track for the lot, before the split.

Enter the split as shares received and shares exchanged. A 4-for-1 split is 4 received and 1 exchanged. A 1-for-10 reverse split is 1 received and 10 exchanged.

Check that the totals match. Share count and per-share figures change. Market value and total cost basis do not.

Frequently asked questions

How does a stock split change shares and price?

Multiply the share count by the shares you receive and divide by the shares you exchange. Divide the price and the per-share cost basis by that same factor. A 4-for-1 split turns 100 shares at $200 into 400 shares at $50. A $150 cost basis becomes $37.50 a share. The position is still worth $20,000, and the total cost is still $15,000.

What do you enter for a reverse split?

Enter fewer shares received than shares exchanged. A 1-for-10 reverse split is 1 received and 10 exchanged. The share count falls and the price rises. The total value and the total cost stay the same.

Is this investment advice?

No. The calculator is for general informational and educational purposes only. A split does not, by itself, change what the position is worth.

Shares after the split

How to adjust a position for a split

Frequently asked questions

Related tools

Related guides

Shares after the split

How to adjust a position for a split

Frequently asked questions

Related tools

Related guides