Assembly Line Balancing Generator
A production line runs at a cycle time: every station gets the same fixed window before the work moves on. Balancing the line means fitting tasks into stations without exceeding that window and without ever putting a task before something it depends on. This generates a task set with precedence rules, balances it, and shows both the station count and the floor the work alone imposes — because the gap between them is precedence, not inefficiency.
What this generator does
Generates tasks with durations and backward-pointing precedence rules, then fills each station with the longest task that is ready and still fits. It reports station loads, idle time, line efficiency and the minimum stations the total work would need.
How to use this tool
- Choose how many tasks and what cycle time each station gets.
- Generate and read the station count against the floor.
- Look at the idle time per station — that is the balance loss.
- Raise the cycle time and watch efficiency rise as throughput falls.
Understanding the controls
- How many tasks
- Between 4 and 24. More tasks usually balance better, because there are more small ones to fill the gaps at the end of a station.
- Cycle time
- How long each station has. Task durations are drawn up to half of it, so no task can ever be impossible to place. A longer cycle means fewer stations and slower throughput.
Common use cases
- Practising line balancing on task sets you did not design
- Producing worked examples for an operations management course
- Showing why precedence forces extra stations beyond the work total
- Generating exercises where the efficiency figure can be checked
- Teaching the trade between cycle time and line length
How this generator works
Stations are filled one at a time. A task is ready when everything it follows has already been placed, and it is added if it also fits in the remaining time; the longest ready task is taken first, since leaving the big ones until last is what strands them. The floor is the total work divided by the cycle time, rounded up — no line can use fewer stations than that, though precedence often forces more. Before display every station is re-totalled against the cycle time, every task is confirmed to be assigned exactly once, and every precedence rule is checked against the station numbers.
Randomness and fairness
Uses your browser's cryptographic random source for durations and precedence by default. A seed reproduces the same problem, deterministically and not cryptographically securely.
For how randomness is produced across the whole site, see how Generate Random works.
Limitations and good to know
- The longest-ready-task rule is a heuristic; an optimal balance can sometimes use one station fewer, and finding it is expensive.
- Every station is assumed equally capable, so a task needing a particular machine or skill cannot be pinned.
- Parallel stations, buffers between stations and rework loops are all outside the model.
- Durations are fixed rather than distributions, so no variability or breakdown is represented.
Privacy and your data
The problem and the balance are computed in your browser, with nothing transmitted, stored or included in analytics.
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