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Convertible Notes vs SAFE: Which Should You Use?

Published April 23, 2026 • 6 min read

When raising an early-stage funding round, founders typically choose between two instruments: convertible notes and SAFE notes. Both are designed to delay valuation until a later priced round, but they work differently and have distinct advantages.

Key Takeaway

SAFE notes are generally simpler and more founder-friendly for early-stage rounds. Convertible notes add debt complexity but may be preferred in certain situations or by certain investors.

What Is a Convertible Note?

A convertible note is a debt instrument that converts to equity in a future financing round. It's essentially a loan that converts to stock instead of being repaid with cash.

Key characteristics:

What Is a SAFE Note?

A SAFE (Simple Agreement for Future Equity) was created by Y Combinator in 2013 as a simpler alternative to convertible notes. It's not debt—it's a warrant that gives the right to purchase equity in a future round.

Key characteristics:

Side-by-Side Comparison

Feature Convertible Note SAFE Note
Type Debt instrument Equity warrant
Interest Yes (2-8%) No
Maturity Date Yes (typically 18-24 months) No
Repayment Risk Must repay if no conversion Never requires repayment
Legal Complexity Higher Lower (standardized)
Document Length 5-10 pages 2-5 pages
Investor Preference Mixed Increasingly preferred

Pros of Convertible Notes

Cons of Convertible Notes

Pros of SAFE Notes

Cons of SAFE Notes

When to Use Convertible Notes

Use Convertible Notes If:

When to Use SAFE Notes

Use SAFE Notes If:

Key Terms to Negotiate

Whether you choose notes or SAFEs, these terms matter:

  1. Valuation Cap: The maximum valuation at which your investment converts. Lower caps are better for investors, higher caps for founders.
  2. Discount: The percentage discount to the next round's price. Typical range: 10-20%.
  3. Pro Rata Rights: Right to invest additional money in the next round to maintain ownership percentage.
  4. Most Favored Nation (MFN):strong> If you give better terms to a later investor, earlier investors get those terms too.
  5. Maturity Date (notes only): When the note must be repaid or converted. Shorter is riskier for founders.
  6. Interest Rate (notes only): Usually 2-8%. Lower is better for founders.

Real-World Example

You raise $500,000 on a SAFE with a $5M cap and 20% discount.

Six months later, you raise a Series A at a $10M pre-money valuation.

The Verdict

For most early-stage startups raising from angels or seed-stage VCs, SAFE notes are the better choice. They're simpler, faster, and don't create repayment risk.

Convertible notes make sense in specific situations—when investors request them, when dealing with debt-focused investors, or when you need the discipline of a maturity date.

💡 Pro Tip

Most startups can raise multiple SAFE rounds (Seed SAFE, Series A SAFE) before doing a priced round. Use our SAFE Calculator to model how multiple SAFEs convert at different valuations.

Calculate Your SAFE Conversion

Model how your SAFE notes will convert at your next priced round with cap, discount, and MFN calculations.

Try SAFE Calculator →
Try it yourself

Use our free SAFE Note Calculator to model how your convertible notes or SAFEs convert at your next priced round. No signup required.

Try SAFE Note Calculator Free →
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