Kanban
Kanban is a visual pull system that controls the flow of work and materials using signal cards. It limits work in process and ensures that production only happens when there is actual demand.
Kanban (Japanese: 'visual card' or 'signboard') was developed at Toyota to control material flow without complex planning systems. A Kanban card signals: 'This part has been consumed -- produce or deliver a replacement.' Nothing is produced without a signal.
The core principle is pull instead of push: Instead of producing based on forecasts and pushing material downstream, the downstream process pulls what it needs. This automatically limits overproduction -- the worst form of waste in Lean thinking.
In modern knowledge work, Kanban boards visualize workflow stages (e.g., To Do, In Progress, Done) with explicit WIP limits per column. When a column reaches its limit, no new work enters until something moves forward.
Kanban exposes bottlenecks naturally: When work piles up before a column, that stage is the constraint. This visibility drives targeted improvement rather than blanket capacity increases.
Practical Example
A machining cell uses a two-bin Kanban system for raw castings. Each bin holds 50 pieces. When operators empty the first bin, the empty bin's Kanban card goes to the supplier area, triggering a replenishment of 50 pieces. WIP never exceeds 100 castings -- previously it was 400+, tying up capital and floor space.
How Leanshift Helps
Leanshift tracks cycle times and WIP levels per process step. This data helps you set optimal Kanban quantities and identify where pull signals should be placed for maximum flow.
Frequently Asked Questions
What is the difference between Kanban and Scrum?
Scrum works in fixed-length sprints with defined scope. Kanban uses continuous flow with WIP limits and no fixed iterations. Kanban is often better suited for operations and maintenance work with unpredictable demand.
How do you determine the right number of Kanban cards?
A common formula: Number of Kanbans = (Daily Demand x Lead Time x Safety Factor) / Container Size. Start with a generous number and reduce gradually to expose problems.
Can Kanban work in office environments?
Absolutely. Digital or physical Kanban boards are widely used in software development, HR, marketing, and administrative processes. The principles of visualization, WIP limits, and pull remain identical.
Related Terms
Lead Time
Lead time measures the total duration from order receipt to delivery -- including all waiting, storage, and transport times. It determines delivery capability.
Heijunka (Production Leveling)
Heijunka smooths production volume and mix over time to eliminate peaks and valleys. It creates a steady, predictable flow that reduces waste and stress throughout the value stream.
One-Piece Flow
One-Piece Flow means processing and passing one unit at a time through all process steps without batching or waiting between stations. It is the ideal state for minimizing lead time and waste.