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The Fragmentation of Time

This interactive tool visualizes how random interruptions destroy deep work capacity. Using Poisson distribution to model interruptions and recovery time, we can see the real impact on productivity over simulated workdays.

Adjust the parameters below to simulate different work environments and see how interruptions affect your ability to achieve deep work.

For a deeper dive into the math behind this simulation, read the full article: The Math of Why You Can't Focus at Work.

Define Your Environment

Parameters
Interruptions / Hour (λ)1.0
Recovery Time (Δ)11 min

Pace: At λ=1, interruptions occur roughly every 60 min.

Cost: With Δ=11m, you lose ~11 min per hour to recovery.

Define Your Goals

What counts as deep work?
How many blocks do you need?
Deep work block: A continuous period of focused work without interruptions.
Daily target: The number of 60-min blocks you need to have a successful day.

Your Likelihood of Success

100%likelihood of achieving a block ≥ 60 min on any given day
45+ min30-45 min15-30 min<15 min

Understanding the Parameters

  • λ (Lambda): Interruptions per hour. Higher values mean more frequent interruptions.
  • δ (Delta): Recovery time in minutes after each interruption. Time needed to regain focus.
  • Threshold: Minimum continuous time (30, 45, or 60 minutes) needed for a "qualifying" focus block.
  • Target: How many qualifying blocks you need per day to consider it a "good day".

Example Personas

  • Deep Work: λ = 0.4/hr, δ = 11min
  • Maker Schedule: λ = 1.0/hr, δ = 11min
  • Manager Schedule: λ = 2.2/hr, δ = 11min
  • Executive Schedule: λ = 3.0/hr, δ = 11min