WIP Limits & Little’s Law Simulator
An animated kanban board where work items flow from backlog through an in-progress column to done. A team of developers shares its capacity across everything in progress, and every extra concurrent item adds a context-switching tax — so cranking up the WIP limit makes each card crawl. Live meters show throughput, average cycle time and work in progress, with a running Little’s Law check (L = λ×W) tying them together. A one-click comparison sweeps WIP limits 1 to 12 with your exact team settings and charts cycle time and throughput against the limit, exposing the sweet spot — and the collapse under heavy multitasking.
Runs 100% in your browser — simulations are computed locally on your device.
Read the full guide to this tool
Notes
- Little’s Law (L = λ×W) is not a model but an accounting identity: average WIP equals throughput times cycle time in any stable system. Fix your throughput and every extra item in progress is pure added waiting time.
- Context switching is the villain: research consistently puts the overhead of each extra concurrent task at 10–20%, which is why "start everything, finish nothing" teams feel busy while shipping little.
- The sweet spot is usually a WIP limit near the number of people: enough to keep everyone busy, low enough that nothing waits half-finished.
- Variability matters — the more item sizes vary, the more a tight WIP limit protects your cycle time. Try it with the variability slider.
- Runs 100% in your browser — simulations are computed locally on your device.
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