5 Whys

5 Whys template you can copy

Use the tool above, or paste this table into Excel, Google Sheets, Word, or Notion. Each row's answer becomes the next row's question, and each answer should name one cause you can check.

Copy this block. The tabs paste into separate cells:

Step	Why?	Answer (one checkable cause)	Evidence
Problem	What happened, and when?
1	Why did it happen?
2	Why?
3	Why?
4	Why?
5	Why?
Fix	What change stops it recurring?	Owner:	Check date:

Filled-in example: Toyota's stopped machine

This is Taiichi Ohno's own example, as quoted by Mark Graban from Ohno's book on the Toyota Production System:

The fix at row 1 is a new fuse. The fix at row 5 is a strainer, and that is the one that stops the machine failing again.

The Kamigo Count: five is not a rule

Five is how many it took in one case. Graban reports Art Smalley's point that Ohno used five "simply because that's how many it took in that particular case at the Kamigo plant." Graban also notes that the first and last answers each hold two causes. Separate them and the same chain has seven whys, not five.

So the template's real rule is one cause per row:

• If an answer contains "and," split it into two rows.
• If you can't point to evidence, you are guessing. Go and check before you ask the next why.
• Stop when the fix is in your control, whether that takes three rows or seven.

When this template is the wrong tool

Use a fishbone diagram when several causes interact. A single chain follows one path, and AHRQ's summary of Alan Card's 2017 BMJ Quality & Safety paper says the tool "tends to simplify complex problems and limit understanding of how processes fail." If a row has two real answers, branch it instead of picking the convenient one.