Html Issue Bot 9000 Lab

Problem Statement

Let's practice using the W3C's HTML Validator!


  1. Correct invalid HTML to be valid

Correct Invalid HTML To Be Valid

In this lab we'll use the W3C Validator to make our invalid HTML happy! You might need to change how you work this problem depending on your work environment. Either way you'll learn to fix invalid HTML.

Tasks for LearnIDE Environment Users

  1. Click the "OPEN IDE" button

Tasks for Local Environment Users

  1. Fork this repository.
  2. Clone your fork locally.
  3. cd into the local repo you just cloned.

In this lesson we'll be taking the provided index.html file and will get feedback from the W3C validator about it.


  1. Open index.html in a browser. See how it, well, doesn't look quite right?
  2. Open index.html in your text editor
  3. Visit the W3C validator at:
  4. Copy the code from index.html and paste it into the text area
  5. Click the large "Check" button
  6. Use the error messages to correct the code your copy of index.html
  7. Repeat steps 3-6 until the Html Validator reports: "Document checking completed. No errors or warnings to show."
  8. Not only is the document now W3C-valid, it no longer looks weird

Submitting the Lab

When your document is valid, go to the terminal and type:


Since you're verifying the HTML structure via W3C, the test here is not robust at all.

To move to the next lesson, type learn submit.


View HTML Issue Bot 9000 on and start learning to code for free.

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