Free tool
5 Whys Root Cause Analysis
Run a structured 5 Whys analysis to find the root cause of an equipment failure.
Problem data
5 times “Why?”
Root cause and corrective action
Result: root cause analysis (5 Whys)
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You enter a problem description and up to five “Why?” answers. The tool builds a visual cause chain (problem → why 1 → … → root cause) and an action plan table: corrective action, owner and deadline. Empty “Why?” rows are left out of the chain. The result can be printed or saved as a PDF.
Illustrative example: problem “bearing failed” → why? “no lubrication” → why? “the maintenance plan had no such item” → root cause “the plan was not updated after the machine was modified”.
Frequently asked questions
How many “why” questions are needed?
Usually three to five – until you reach a cause that can be eliminated by changing the process.
What is the difference between a symptom and a root cause?
A symptom is what you see (the bearing failed); the root cause is why it happened and what to change so it does not recur.
Who should take part in the analysis?
The operator, the maintenance technician and the shift or maintenance manager – this gets the analysis to the real cause.
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Methodology and limitations
Methodology based on standard industry calculations and Maintest’s practical industrial experience. This tool provides a planning estimate and does not replace project-specific engineering assessment. This tool is a screening and planning aid developed by Maintest. Results are indicative and depend entirely on the figures and answers you enter. They are not an engineering calculation, a safety assessment or a substitute for the manufacturer’s instructions, applicable standards or professional judgement. Weights, benchmarks and default values are Maintest planning assumptions and can be adjusted to your situation. Do not use this tool as the only basis for safety-critical decisions such as lifting, electrical work or lockout procedures.
Tool version 1.0 · Updated October 2026
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