Margin of safety is the distance between your current revenue and your break-even point, expressed as a percentage.
Margin of Safety = (Actual Revenue − Break-Even Revenue) ÷ Actual Revenue × 100
If you're doing $60,000/month and your break-even is $40,000: - Safety margin = ($60,000 − $40,000) ÷ $60,000 = 33.3%
What the percentages mean
Below 0%: Operating at a loss. Burn is accelerating. Without intervention, runway is finite.
0–10%: Technically profitable, but fragile. A churn spike or one unexpected expense pushes you into loss. Not a state to hire from.
10–25%: Moderate resilience. Can weather a normal bad month. Appropriate for steady-state businesses but limited investment capacity.
25%+: Healthy. Revenue significantly cushions fixed costs. Can absorb team growth, churn spikes, and market downturns.
How investors use margin of safety
Early-stage investors look at margin of safety trajectory, not just the snapshot: - A business at 5% safety margin growing it to 30% over 12 months is compelling. - A business at 25% declining toward 10% is a warning sign.
Margin of safety combined with growth rate tells the complete story of unit economics sustainability.
Operational decisions driven by safety margin
Hiring decisions: Only hire when safety margin is comfortable enough to absorb the new fixed cost. Adding a $15k/month hire when you have $15k in safety margin brings you back to break-even.
Fundraising timing: Raise when safety margin is positive and trending up. Fundraising from a strong position gives negotiating leverage.
Pricing confidence: A high margin of safety gives room to experiment with pricing without existential risk.
Calculate yours with the free Break-Even Revenue Calculator.