Pro rata calculator
Pro rata rights let an investor put money into later rounds to keep their percentage. The amount is their share × the size of the new round.
The formula
Pro rata rights = share you own × size of the next round
Worked example: £200,000
The example uses the guide's seed round, £200,000 for 20%, with a matching cap table, exit, fund and market.
- 10.0% × £2,000,000 = £200,000 to keep your share
Work out your pro rata rights
Until you type a figure, the results show an example business. Fill in only what you know: from then on every result uses your figures alone, and nothing you type leaves your browser.
Pro rata amount for the example
Example£200,000
- 10.0% × £2,000,000 = £200,000 to keep your share
Formula: Share you own × size of the next round.
- Your share if you do not invest
- 7.5%
Everything your numbers show
For the example business: 27 of 27. Type your own figures to replace them. Select one for its page.
- Valuation£1,000,000post-money
- Pre-money valuation£800,000
- Post-money valuation£1,000,000
- Equity20.0%Equity sold
- Dilution70.0%kept by existing shareholders, down from 100.0%
- Option pool142,857new pool shares
- Fully diluted60.0%Fully diluted ownership
- SAFESimple agreement for future equity89,286shares
- Loan note96,429shares
- Pro rata rights£200,000Pro rata amount
- Liquidation preference£1,000,000to the investor
- Vesting180,000after 18 months
- Cliff120,000at month 12
- SEISSeed Enterprise Investment Scheme£10,000
- EISEnterprise Investment Scheme£6,000
- VCTVenture capital trust£4,000
- TAMTotal addressable market£240,000,000a year
- SAMServiceable available market£60,000,000a year
- SOMServiceable obtainable market£3,000,000a year
- Down roundDown round
- Up roundDown round
- Flat roundDown round
- MOICMultiple on invested capital2.80x
- IRRInternal rate of return22.9%a year
- TVPITotal value to paid-in capital1.50x
- DPIDistributions to paid-in capital0.40x
- Dry powder£24,000,000
How to read your result
An investor who skips their pro rata is diluted like everyone else. Founders should know who will take up their rights before the round.
Watch out for
Check whether the right covers the whole round or only part of it: some agreements cap it.
Last checked . Estimates only, not financial, tax or legal advice: check your accounts and documents, and take advice before you act. More terms in the startup glossary.