A standard SAFE is generally not debt and has no ordinary interest or maturity date. It provides contractual rights to future equity and specified outcomes for other events. Read the signed form because amendments and different templates can change those rights.

Do the valuation cap and discount both apply?

When the instrument offers both as alternatives, compare the cap price with the discounted round price and use the lower price. Do not automatically apply the discount to the cap price. The capitalization definition and signed conversion language determine the calculation.

Does all convertible note interest convert at the same price as principal?

Not always. Some notes convert principal and accrued interest at the same price; others treat interest differently or pay it in cash. Confirm the interest rate, accrual method, dates, and conversion terms before calculating shares.

What happens if there is no priced round before a note matures?

Maturity does not guarantee automatic conversion. The note may call for repayment, permit conversion, or require an agreed extension. Ask counsel to review the actual maturity and default provisions before the date arrives. A standard SAFE generally has no comparable maturity deadline.

Can the SAFE calculator model a convertible note?

The calculator models SAFEs only. It does not accrue note interest, interpret maturity or financing thresholds, or apply separate conversion terms to principal and interest. Use it for SAFE scenarios and reconcile notes separately from their signed terms with counsel.

Guide

SAFE versus convertible note: how each converts

By the Vanward team · Last updated October 24, 2026

A SAFE is an agreement for future equity that generally has no interest or maturity date. A convertible note is debt, usually with interest and a maturity date, that can convert into equity under specified conditions. At a priced financing, each converts the amount eligible under its terms into shares at a conversion price. A valuation cap or discount can reduce that price. A note may also convert accrued interest, so the amount becoming shares can exceed the cash originally invested. The signed instrument controls the trigger, price, share class, and treatment of interest.

Compare the obligations before comparing the conversion price

Term	Typical SAFE	Typical convertible note
Form	Contract for future equity	Debt that can convert into equity
Interest	None	Accrues at the stated rate
Maturity	No fixed maturity date	A stated date with contractual consequences
Financing trigger	Equity financing as defined in the SAFE	Often a qualified financing above a stated threshold
Amount converting	Investment amount	Principal plus any interest eligible to convert
Price terms	Cap, discount, or other signed terms	Cap, discount, or other signed terms

These are common structures, not a substitute for the document. Both can also address a sale or dissolution. A conversion can issue the round's preferred stock or a separate series with different economic terms. Keep those details beside the ownership calculation.

Work from the trigger to the shares

First confirm that the financing satisfies the instrument's conversion trigger. Then identify the amount eligible to convert. Calculate the cap price using the instrument's definition of company capitalization, and the discount price using the round price. Where the terms provide the better of the two, the lower price produces more shares. Divide the eligible amount by that price.

A cap is a conversion pricing term, not an appraisal of the business. A pre-money SAFE cap and a post-money SAFE cap use different capitalization definitions. Multiple instruments and a pool increase can change the denominator, so do not infer final ownership from the cap alone.

A discount-only example shows why interest matters

Consider two separate fictional investments of $100,000, one under a SAFE and one under a note. Each has a 20 percent discount and no cap. Assume a financing that triggers conversion at a $2.00 round price. The conversion price is $2.00 times 80 percent, or $1.60. The note accrues simple interest at 8 percent for exactly one year, and its terms convert both principal and interest at that same price.

Calculation	SAFE	Convertible note
Original investment	$100,000	$100,000
Interest eligible to convert	$0	$8,000
Total converting	$100,000	$108,000
Conversion price	$1.60	$1.60
Shares issued	62,500	67,500

The note receives 5,000 more shares because interest also converts in this example. A different interest period or treatment changes the result. Neither share count alone tells you final ownership: divide by the total shares after all conversions, the pool adjustment, and the new financing shares.

A post-money SAFE cap fixes a different reference point

In a separate example matching the SAFE calculator, begin with 9,000,000 existing shares, one $1,000,000 post-money SAFE at a $10,000,000 cap, no discount, and no pool. At a $20,000,000 round pre-money valuation, the cap sets a $1.00 conversion price. The SAFE receives 1,000,000 shares and owns 10 percent before new money. A $5,000,000 investment at the $2.00 round price adds 2,500,000 shares, reducing the SAFE to 8 percent afterward.

Use the SAFE conversion calculator to compare pre-money and post-money SAFEs, caps, discounts, and a pool together. It models SAFEs, not notes, and uses stated capitalization assumptions. A real instrument may treat pool increases or promised options differently.

Prepare one conversion schedule from the signed instruments

Record each investment amount, instrument version, cap basis, discount, trigger, and share class. For notes, add issue date, interest method, accrued interest, maturity, and any amendments. Have counsel reconcile the schedule to the closing cap table before the round closes. A spreadsheet cannot resolve terms that the documents leave different.

Questions founders ask

Is a SAFE a loan?: A standard SAFE is generally not debt and has no ordinary interest or maturity date. It provides contractual rights to future equity and specified outcomes for other events. Read the signed form because amendments and different templates can change those rights.
Do the valuation cap and discount both apply?: When the instrument offers both as alternatives, compare the cap price with the discounted round price and use the lower price. Do not automatically apply the discount to the cap price. The capitalization definition and signed conversion language determine the calculation.
Does all convertible note interest convert at the same price as principal?: Not always. Some notes convert principal and accrued interest at the same price; others treat interest differently or pay it in cash. Confirm the interest rate, accrual method, dates, and conversion terms before calculating shares.
What happens if there is no priced round before a note matures?: Maturity does not guarantee automatic conversion. The note may call for repayment, permit conversion, or require an agreed extension. Ask counsel to review the actual maturity and default provisions before the date arrives. A standard SAFE generally has no comparable maturity deadline.
Can the SAFE calculator model a convertible note?: The calculator models SAFEs only. It does not accrue note interest, interpret maturity or financing thresholds, or apply separate conversion terms to principal and interest. Use it for SAFE scenarios and reconcile notes separately from their signed terms with counsel.