Pre & Post-Money Valuation Calculator
Choose a mode, enter the two required values, then calculate the remaining valuation fields.
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Use this Pre & Post-Money Valuation Calculator to estimate the relationship between a startup’s investment amount, investor ownership, pre-money valuation, and post-money valuation in a simple priced equity financing round.
Important: This calculator shows simplified valuation and dilution math. Actual financing outcomes can differ because of option pools, existing investors, SAFEs, convertible notes, preferred-share terms, warrants, and other cap-table provisions.
Pre-Money and Post-Money Valuation
Post-money valuation = pre-money valuation + new investment
Therefore:
Pre-money valuation = post-money valuation − new investment
Pre-money valuation represents the agreed company valuation before the new financing is added. Post-money valuation represents the valuation after including the new investment.
Investor Ownership
In a simple priced round:
Investor ownership % = investment ÷ post-money valuation × 100
If the investment and desired investor ownership are known:
Post-money valuation = investment ÷ investor ownership
Pre-money valuation = post-money valuation − investment
Investor ownership must be entered as a decimal when used directly in these formulas. For example, 20% = 0.20.
Finding Investment From Ownership
If post-money valuation and investor ownership are known:
Investment = investor ownership × post-money valuation
If pre-money valuation and desired post-money ownership are known:
Investment = investor ownership × pre-money valuation ÷ (1 − investor ownership)
The simplified remaining ownership of all pre-round shareholders is:
Remaining ownership = 100% − new investor ownership
Worked Example
Suppose a startup has a $4,000,000 pre-money valuation and receives a $1,000,000 investment.
Post-money valuation:
$4,000,000 + $1,000,000 = $5,000,000
Investor ownership:
$1,000,000 ÷ $5,000,000 × 100 = 20%
Simplified remaining ownership for the pre-round shareholders:
100% − 20% = 80%
So the financing implies a $5 million post-money valuation, with the new investor receiving 20% and existing shareholders collectively retaining 80%, before considering other dilution or cap-table effects.
Why Pre-Money vs. Post-Money Matters
A valuation must be clearly identified as pre-money or post-money because the same investment can produce different ownership percentages.
For example, a $1 million investment at a $5 million pre-money valuation produces:
Post-money valuation = $6 million
Investor ownership = $1 million ÷ $6 million ≈ 16.67%
But a $1 million investment at a $5 million post-money valuation represents:
$1 million ÷ $5 million = 20%
The wording of the valuation therefore has a direct effect on implied dilution.
Important Notes
- The calculator is designed for a simple priced equity financing round.
- Investor ownership is calculated using post-money valuation, not pre-money valuation.
- The remaining-ownership result represents all existing shareholders collectively; it is not necessarily the ownership of one founder.
- Employee option pools or increases to an option pool can materially change dilution.
- SAFEs and convertible notes may convert using valuation caps, discounts, accrued interest, or other terms and require separate calculations.
- Preferred shares may include liquidation preferences, anti-dilution protection, voting rights, participation rights, and other economic terms that are not reflected here.
- The calculator does not build a fully diluted cap table or allocate dilution among individual shareholders.
- A mathematically implied valuation does not determine whether a company’s valuation is fair or whether an investment is appropriate.
- The currency selector changes the displayed currency only and does not perform exchange-rate conversion.
- Actual financing transactions should be reviewed using the applicable term sheet, cap table, and legal documents.