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Customer Concentration Calculator

Are you too dependent on one customer?

Enter your top customers by revenue to see your concentration risk. If your biggest customer left tomorrow, would your business survive?

Enter Your Customers

Enter annual revenue by customer. Include your top 5-10 customers to get an accurate picture.

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Why Customer Concentration Matters

Customer concentration is a hidden risk that kills businesses. When one customer represents too much of your revenue, you don't have a business—you have a job with one employer who can fire you at any time.

The SEC requires public companies to disclose any customer representing 10% or more of revenue as a material risk. Private equity firms and lenders use the same threshold when evaluating acquisition targets.

The Concentration Zones

  • Critical (50%+): One customer controls your fate. If they leave, your business may not survive.
  • Warning (25-50%): Significant exposure. Losing this customer would hurt badly but wouldn't be fatal.
  • Healthy (Under 25%): Diversified. No single customer loss would be catastrophic.

How to Reduce Concentration

  1. Don't turn away small customers — They reduce your concentration even if margins are lower
  2. Market consistently — Don't stop prospecting when you're busy
  3. Raise prices on your biggest customer — Either they pay more or you have incentive to replace them
  4. Build relationships, not dependencies — Great service doesn't require letting one customer dominate

The Hidden Danger

Concentration often happens gradually. A small customer becomes a big customer. You hire people to serve them. Then you're trapped—you can't afford to lose them, and they know it.

Check your concentration quarterly. The time to fix it is before it becomes a crisis.

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