Root cause analysis, from problem to solution

Seven methods, each one end to end: the guide, a worked example, the template you hand in, and the page on facilitating the session — plus eight tools that run in your browser. Free, no login. What you type stays in the tab.

Problem Solution People Method Machine Measurement Material Environment
7methods, each end to end
68practitioner-written guides
57template files, Excel, Word and PDF
8tools that run in your browser

What this site is

5xWhys is an independent library of root cause analysis methods, maintained by one practitioner with ten years in operations and quality across regulated manufacturing, healthcare operations and software reliability. It covers seven methods in 68 guides, 57 downloadable template files and eight browser tools, written for whoever has to explain what went wrong and show it was fixed. You do not need a quality background: 5 Whys takes about ten minutes to learn, and the same pages are used by operations and support leads, project managers, clinicians and consultants as much as by quality and reliability engineers. Everything is free and works without an account; the tools keep nothing you type. More about who builds this and why →

Start here

Three ways in — pick the one that matches your next hour

Most people arrive mid-problem. No tour, no signup wall: go straight to the thing you need.

Seven methods, each one end to end

Every method here has the same four pieces: a guide that explains it, examples with real numbers, a template you can download, and a page on how to run the session with a team. Six of the seven also have a tool that runs in your browser; the other two tools — the Problem Statement Generator and the Cost of Poor Quality Calculator — work with any method, which makes eight. Pick the row that matches your problem.

8D problem solvingFormal customer-facing corrective action, D0–D8. Automotive and aerospace supplier quality. 8 articles.
5 WhysOne incident, one causal chain, the root cause before the next shift starts. 14 articles.
Root cause analysisThe method-agnostic process: problem statement, evidence, corrective action, verification. 22 articles.
Fishbone / IshikawaMap every candidate cause across 6M or 6P categories before narrowing down. 6 articles.
FMEARisk before the failure happens: Severity × Occurrence × Detection, ranked for action. 6 articles.
Pareto analysisWhich 20% of causes make 80% of the problem, so you know what to fix first. 5 articles.
A3 thinkingToyota’s one-page problem-solving canvas and the coaching loop around it. 5 articles.

Templates — 19 of them, 57 files

Every template comes in Excel, Word and PDF, with a page that shows a filled-in example before you download anything. No email, no signup.

8D report template

D0–D8 in the Ford AIAG layout, customer-ready

RCA report template

Findings, actions, owners, verification

5 Whys template

Why-chain plus countermeasure table

Fishbone / Ishikawa template

6M layout, print-ready A3

FMEA template

S×O×D scoring with action priority

Pareto analysis template

Data table with cumulative %

A3 template

Toyota one-pager, seven sections

CAPA form

Correction, corrective and preventive action, with effectiveness check

Blameless postmortem template

Timeline with sources, contributing factors, typed actions

Is / Is Not worksheet

Problem specification for 8D step D2

5W2H worksheet

Seven questions with an evidence column

Corrective action plan

Tracker with owners, criteria and impact-effort matrix

Incident investigation report

Nine sections plus a first-24-hours EHS checklist

Kaizen event agenda

Five-day agenda plus a role card

Control plan

Eleven columns, three phases, reaction plan

SIPOC

Process scope on one page, with output requirements

8D progress tracker

Gate criteria per discipline, owners, and the customer clock

8D pre-submission checklist

The 24 checks a customer reviewer applies before accepting a report

RCA meeting agenda

60 and 90 minutes, block by block, with the attendee sheet

Eight tools, nothing to install

Each one runs in the tab, saves your progress in the browser and exports a plain file for your own report. Nothing is sent to a server.

8D Report GeneratorD0–D8 with occurrence and escape kept apart, and a rejection-risk check. PDF / JSON.
Open →
5 Whys Analysis ToolGuided why-chain with checks that stop you at symptoms and blame. PNG.
Open →
Fishbone Diagram MakerIshikawa cause-and-effect diagrams — 6M, 6P or custom categories. PNG.
Open →
Pareto Chart Maker80/20 ranking with the cumulative line drawn for you. PNG.
Open →
FMEA / RPN CalculatorSeverity × Occurrence × Detection with a Pareto-ranked RPN review. CSV / PNG.
Open →
Problem Statement GeneratorRed-flag validation catches blame, hidden solutions, vague wording. TXT / PNG.
Open →
RCA Method SelectorFour questions → the right method, its pairing, the 8D/A3 wrapper. Recommendation.
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Cost of Poor Quality CalculatorRework, scrap, escapes and the firefighting hours nobody books. Annual cost.
Open →

Root cause analysis guides, examples and comparisons

Written for people who have to run the session on Monday, not for people writing a thesis.

All 68 articles →

Workshop Kit · for facilitators

If you run the session, not just fill in the form: the Workshop Kit.

Field-tested agendas, a co-brandable deck, crisis cards for the moments that derail sessions, and the follow-up system that makes results stick. For people who facilitate root cause analysis.

See the Workshop Kit →

Frequently asked questions

Which method should I use — 5 Whys, Fishbone, FMEA or 8D?

Single clear failure with a short chain: 5 Whys. Many candidate causes and a group in the room: Fishbone. Ranking what to fix first: Pareto. Risk before the failure happens: FMEA. Customer-facing corrective action with an audit trail: 8D. The method selector asks four questions and decides for you.

Is it really free, and what is the catch?

The tools, the 57 templates and all 68 guides are free with no account. There is one paid product — a workshop kit for consultants who run RCA sessions professionally. Nothing on the free side is degraded to sell it.

Do you store what I type into the tools?

No. The tools run entirely in your browser; the analysis is never sent to a server. That is also why they keep working offline once the page has loaded.

Can I use the templates at work, or with clients?

Yes — internal use and client work are both fine, including editing and re-branding the files. Reselling the templates as your own product is not.

Can I export the analysis into a report?

Each tool exports what fits it: PNG for diagrams, CSV for scored data, PDF for the 8D report. The exports are plain files, made to be pasted into your own report or QMS record.

Who writes this?

One practitioner with ten years in operations and quality across regulated manufacturing, healthcare operations and software reliability. Every worked example comes from real project work; AI helps with editing, not with the analysis.