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Value Stream Map Builder

Build a graphical current-state or future-state map, edit process data boxes, track inventory between steps, and calculate takt, lead time, process cycle efficiency, bottlenecks, waste, capacity, and rolled throughput yield.

Live Tool

Map controls

Core formula: Takt = available time / customer demand

Calculated Flow Metrics

Value stream summary

Graphical Map

Drag process boxes and edit the selected data box

Selected Process

Data box

How to Use This Value Stream Map Builder

Start with customer demand and the available production time after breaks, meetings, and expected downtime. Add each major process step in sequence, then enter the actual observed data from the point of work. The map calculates takt time, flow capacity, lead time, process cycle efficiency, and rolled throughput yield while keeping the process boxes movable on the visual map.

Formula Reference

Metric Formula Purpose
Takt time Available production seconds / customer demand Defines the required customer pace.
Inventory days Inventory between steps / daily demand Converts WIP into waiting time.
Process cycle efficiency Value-added time / total lead time Shows how much of the value stream is truly value-added.
Rolled throughput yield Product of each step yield Estimates the probability that a unit flows through all steps without defect.
Step capacity Available seconds x uptime / cycle time Identifies the lowest-capacity process step.

Worked Example

If demand is 480 units per day and the team has 395 net available minutes after breaks and downtime, takt is 49.4 seconds per unit. A process with a 72-second cycle time and 86% uptime has an effective cycle time above takt, so it becomes a constraint. If 160 units are waiting after that process, the queue adds 0.33 days of lead time before the next step begins.

Interpretation Guide

  • If effective cycle time exceeds takt, the step is a bottleneck or needs balancing, method improvement, staffing review, or demand segmentation.
  • If lead time is dominated by inventory days, attack batch size, scheduling logic, FIFO discipline, and replenishment signals before optimizing touch time.
  • If process cycle efficiency is very low, the value stream is mostly waiting, queueing, movement, rework, or other non-value-added delay.
  • If rolled throughput yield is low, quality loss is multiplying across the stream even if each single step looks acceptable by itself.

FAQ

Should a Value Stream Map include every single task?

No. A VSM should show the major flow steps, inventory points, information flow, and key operating metrics. Detailed work elements belong in standard work, job breakdown sheets, or process maps.

Should I use observed data or standard times?

Use observed current-state data when diagnosing the existing value stream. Use planned standard times only when designing or validating a future-state map.

How does VSM connect to takt time?

Takt time sets the required pace. Each process step should be compared to takt so the team can see constraints, overproduction risk, and staffing or balancing gaps.

What is the most common VSM mistake?

The most common mistake is drawing a clean map without verifying data at the point of work. A useful VSM is an evidence model, not a conference-room diagram.

Can I save the map?

Yes. Use Save and Load for browser storage, or Export JSON and Import JSON if you want to move the map between computers or keep it with project files.

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