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Bus Factor Calculator

Calculate your team's bus factor and knowledge concentration risk. Identify critical knowledge silos before they become problems.

Our Take

Bus factor is really a 'knowledge distribution' metric. A bus factor of 1 isn't bad because someone might leave—it's bad because knowledge silos slow everyone down every day.

When only one person understands a critical system, every question, every bug, every decision routes through them. This creates bottlenecks during normal operations, not just during emergencies. Teams with low bus factors experience longer incident resolution times, slower feature development, and higher stress on key individuals—regardless of whether anyone actually leaves.

"Codebases with bus factor 1 on critical modules have 3x longer incident resolution times."

— Industry research on knowledge distribution and incident response

Enter Your Team Data

Key Capabilities

Critical Systems/Modules

Optional: List specific critical areas and how many people can maintain each

Enter your team size and at least one capability metric to see your bus factor analysis.

About Bus Factor

The bus factor (also known as the "lottery factor" or "truck factor") is the minimum number of team members who would need to suddenly disappear before critical knowledge is lost. It measures your team's resilience to unexpected departures, whether from resignations, illness, promotions, or winning the lottery.

Why It Matters

  • • Business continuity and risk management
  • • Reduced stress on key individuals
  • • Better vacation coverage and work-life balance
  • • Faster onboarding for new team members
  • • More flexible team assignments

How to Improve

  • • Pair programming and mob programming
  • • Comprehensive documentation and runbooks
  • • Cross-training and rotation schedules
  • • Code reviews as learning opportunities
  • • Regular knowledge-sharing sessions
Bus Factor 1

Critical - Single point of failure

Bus Factor 2

High Risk - Still vulnerable

Bus Factor 3-4

Medium - Some resilience

Bus Factor 5+

Healthy - Well distributed

Frequently Asked Questions

Bus factor (also called truck factor or lottery factor) is the minimum number of team members who would need to suddenly disappear before a project or team loses critical knowledge and ability to function. A bus factor of 1 means a single person holds critical knowledge that nobody else possesses. The term comes from the morbid question: "How many team members would need to be hit by a bus before the project fails?" It's a key metric for measuring organizational risk and knowledge distribution.

Want to track this automatically?

CodePulse connects to your GitHub and calculates these metrics in real-time. No more manual data entry or spreadsheets.

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