SAFE & Convertible Note Conversion Calculator

See what your SAFEs and notes cost you at conversion.

Round pre-money valuation

New money raised in the round

Pre-round fully-diluted shares

Founder shares (of the above)

Conversion date (notes accrue interest to it)

Converting instruments

SAFE 1

Instrument

Investment amount

SAFE type

Valuation cap (blank = none)

Discount % (blank = none)

MFN — no cap, no discount; inherits the best terms of the other SAFEs in this scenario

Output

Scenario from your inputs

Conversion preview

No value yet

An estimate from the figures you enter. Not legal, tax or investment advice.

How this is calculated

Round price per share: Pre-money valuation ÷ pre-round fully-diluted shares, including the option pool and excluding converting instruments.
Conversion price — the lower-of rule: Each instrument converts at the lower of its cap price and its discount price (round price × (1 − discount %)). With neither, it converts at the round price.
Post-money SAFE cap price: Post-money cap ÷ capitalization just before the round, including converting SAFEs and the option pool but not new money. With t = Σ(investment ÷ cap) over capped post-money SAFEs: cap × (1 − t) ÷ pre-round fully-diluted shares.
Pre-money SAFE cap price: Pre-money cap ÷ pre-money fully-diluted capitalization, excluding converting instruments.
Convertible note interest (ACT/365): Simple: principal × rate × days ÷ 365. Compound: principal × ((1 + rate)^(days ÷ 365) − 1). Principal plus interest converts at the lower-of rule. Example: $300,000 at 8% for 367 days accrues $24,131.51.
MFN (most favored nation): An uncapped, undiscounted MFN SAFE takes the lowest conversion price among the other SAFEs in the scenario when that is below the round price; otherwise the round price.
Shares and dilution: Shares = floor(amount ÷ conversion price). Ownership = shares ÷ post-round fully-diluted shares. Founder dilution = founder % before − founder % after.