Who suffers more dilution under Post-Money SAFEs?

Founders absorb more dilution under Post-Money SAFEs because each SAFE's ownership is fixed, meaning subsequent SAFEs dilute only the common stock rather than prior SAFE holders.

Updated: August 2026 • Verified v1.2

Y Combinator SAFE Note (Pre-Money vs Post-Money) Dilution Calculator

Finance & MathPopular

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Post_SAFE_Pct = Amount / Post_Cap; Pre_SAFE_Pct = Amount / (Pre_Cap + Total_SAFEs)

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Understanding Your Results

Models multiple SAFE notes, valuation caps, and option pool expansion side-by-side across Pre-Money and Post-Money models, quantifying the exact percentage dilution penalty experienced by founders.

Practical Guidance & Next Steps

In Post-Money SAFEs, each investor receives a guaranteed fixed percentage ownership that is non-dilutive to other SAFEs. This transparency protects investors but concentrates all pre-Series A dilution exclusively onto founders.

What is this?

A venture capital equity calculator that models dilution differences between YC Pre-Money and Post-Money Simple Agreements for Future Equity.

How does it work?

1. Enter investment amounts and valuation caps for your SAFE notes. 2. Input Series A round valuation and option pool target. 3. Compare post-financing cap table percentages between Pre-Money and Post-Money SAFEs.

Why use it?

Prevents founders from accidentally surrendering excessive equity during seed fundraising rounds.

Technical Scope & Calculation Limitations

Standard Y Combinator open-source SAFE legal framework model.

Frequently Asked Questions

YC introduced Post-Money SAFEs in 2018 to eliminate the confusion of SAFE stacking, ensuring that both founders and investors know the exact ownership percentage being sold immediately upon signing.

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