To calculate a SAFE conversion using a valuation cap, follow these steps: 1. Determine the valuation cap from the SAFE agreement. 2. Identify the total post-money valuation of the company at the next equity financing round. 3. Calculate the conversion price by dividing the valuation cap by the company's fully diluted capitalization at the time of conversion. 4. Convert the SAFE investment amount into equity by dividing the investment amount by the conversion price. This results in the number of shares the SAFE converts into.