On the Hypertext Markup Language (HTML)

The 6 Ways of Writing HTML (and Their Combinations)

The 6 General Ways of Writing HTML

1. Unsystematic

2. Valid

3. Semantic

4. Accessible

5. Required-Only

6. Hyper-Optimized

The 19 Combinations of Writing HTML

Popular Combinations of Writing HTML

Recommended Combinations of Writing HTML

Write HTML, the HTML Way (Not the XHTML Way)

HTML, XHTML, HTML

The XHTML Way of Writing HTML

The HTML Way of Writing HTML

Examples

Write HTML, the HTML Way

“HTML First” Is Not HTML First

What Is HTML First?

On Writing Better Markup

5 Ways to Reduce HTML File Size on Your Website, Step 0

HTML and Performance: Leave Out Optional Tags and Quotes

Contesting the Argument

Saving the Argument

Leave Out Optional Tags and Quotes

Leaving Out Optional Markup in Practice

Optional HTML: Everything You Need to Know

Optional Tags

Optional Quotes

Attribute Value Defaults

Appendix I: Risks

Appendix II: Tooling

An HTML Optimizer’s Config for HTML Minifier

Defensive Optimization

Update (September 18, 2024)

Update (October 15, 2025)

Update (January 19, 2026)

The Most Minimal Valid HTML Document

The Magic of the Most Minimal HTML Possible (and Why We Don’t Make Use of It)

Notes on HTML 3.2

HTML Statistics: 5 Take-Aways

On HTML (and HTML in 2020)

HTML 2022: 20 Additional Observations From Analyzing the Web Almanac Data

20 More Observations from 30 Sheets of Data

Where Has All the Valid HTML Gone

2021: 98% of the Top 100 U.S. Websites Use Invalid HTML

2025: 0 of the Global Top 200 Websites Use Valid HTML

Analysis

HTML Conformance in 2025

HTML Conformance Over Time

Notes and Observations

Interpretation

Testing 10 JavaScript Frameworks on Their HTML Defaults

Modern JavaScript Frameworks and Their HTML

Why Out-of-the-Box HTML Matters

Observations and Conclusion

What Is HTML Optimization? What Is It Not?

Existing Definitions

Another Definition

What HTML Optimization Is

What HTML Optimization Is Not

The HTML History and Optimization Cheat Sheet

A Node and Command Line Tool to Find Obsolete HTML

HTML Minifier Next (a Maintained Fork of HTML Minifier)

Stop Closing Void Elements

Optional “@lang”

Comparing Page Language Declaration Setups in Screen Readers

Update (November 30, 2021)

Declaring Page Language—and Declaring Changes in Language

Focus on Changes in Language

Minimal HTML and Marking up Changes in Language

Use the “i” Element, and Use It Appropriately

Know the “search” Element

The 9 HTML Elements That Have an Attribute of the Same Name, or: The 9 Attributes That Have an Element of the Same Name

A Problem With Link Relationships

What’s the Problem?

If You Still Choose to Make More Use of rel

Minimal Social Markup

Requirements

Social Markup

Problems

Update (November 20, 2022)

Challenge Yourself, Even When It’s Art

Order Force in HTML?

HTML—the Most Difficult Programming Language in the World

On the Uniting Power of a Commitment to HTML Conformance

We Need to Talk More About Conformance, if We Want to Stop Fantasy HTML

How Often Should We Speak About HTML Conformance?

No Surprises, Still Disappointing, Commerce ≠ Community

HTML Conformance: A Comparison of 6.5 npm Validator Packages (With 1.5 Recommendations)

The Reviews

HTML-validate

W3C HTML Validator

html-w3c-validator

html-validator

The Nu Html Checker (v.Nu)

html-validator

HTMLHint

A Summary

Making the Web Developer’s Pilgrimage

A Pilgrimage, What For?

About My Own Pilgrimage

On the Peculiarities of Counting the Number of HTML Elements