Corporate action calculator
See exactly what a bonus, split, rights issue or buyback does to your holding, and stop treating any of them as free money.
Runs entirely in your browser — nothing you type is sent anywhere. Educational only, and not investment advice.
How to use this calculator
Each step names a control you will find on screen above.
- Shares you hold and Price per share
Your position before the action. Note the total value — this is the figure to watch through everything that follows.
- Pick an action
Bonus, split, rights or buyback. The share count and price both change; the total value is the thing to check.
- Compare before and after
For a bonus and a split, the total is identical. Nothing was created — the same pie was cut into more slices.
- Note what changes for tax
A bonus resets your average cost and starts a fresh holding-period clock on the new shares, which has real consequences when you sell.
Worked example: A 1:1 bonus on a ₹80,000 holding
You hold 100 shares at ₹800. The company announces a 1:1 bonus — one free share for each held.
What to enter
- Shares you hold
- 100
- Price per share
- ₹800
- Action
- Bonus 1:1
What it shows you
- Before
- 100 × ₹800 = ₹80,000
- After
- 200 × ₹400 = ₹80,000
- Value created
- ₹0
- Your ownership share
- Unchanged
- Cost basis
- Halved, to ₹400 per share
Where this is taught
A calculator gives you a number. These explain what the number means and when it misleads you.
- Market Basics10 minCorporate actions: bonus, split, dividend, rights, buybackFive things a company can do to its own shares — which ones create value, which ones just re-cut the pie, and what the dates actually mean.
- Market Basics12 minBuybacks, OFS and delisting: when the company comes to youSometimes it is the company or the promoter placing the order, not you. What each event means, when to participate, and what the acceptance ratio really decides.
- Risk & Psychology13 minDeciding against somebody else’s clockRights issues, buybacks, open offers and launch windows all arrive with a date you did not choose. What a deadline does to judgement, and the preparation that makes it harmless.
- Fundamental Analysis13 minMergers, demergers and value unlockingMost acquisitions destroy value for the acquirer and most demergers create it. How to read a deal announcement, and what the share entitlement ratio actually means for you.
- Market Basics11 minRights issues, entitlements and renunciationThe company offers you more shares at a discount. Three choices, and doing nothing is the only one that is definitely wrong.