Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
CSS Specificity Calculator
Calculate, compare, and understand CSS selector specificity.
- Home
- Web Dev
- CSS Specificity Calculator
0
Inline
( class="page_speed_8" )
0
ID
( #id )
0
Class / Attribute
( .class, [attr] )
0
Element
( div, ::before )
Selector Visualization
What is CSS Specificity?
CSS specificity determines which styles are applied when multiple rules target the same element. It is calculated as a four-part weight:
| Category | Examples | Weight |
|---|---|---|
| Inline styles | class="page_speed_9" | 1, 0, 0, 0 |
| ID selectors | #header, #main-content | 0, 1, 0, 0 |
| Class, attribute & pseudo-class | .container, [type="text"], :hover | 0, 0, 1, 0 |
| Elements & pseudo-elements | div, h1, ::before, :first-line | 0, 0, 0, 1 |
The !important declaration overrides all specificity calculations and should be used sparingly.
How to Use
- Enter a CSS selector — Type any CSS selector in the input field. Click Examples to try predefined selectors.
- Calculate — Click Calculate Specificity to see the breakdown of inline, ID, class/attribute, and element counts.
- Compare — Optionally enter a second selector to compare which one has higher specificity.
- Visualize — View a color-coded breakdown showing which parts contribute to each specificity category.
Frequently Asked Questions
Why does specificity matter?
Understanding specificity helps you debug CSS conflicts and write more maintainable stylesheets. When two selectors target the same element, the one with higher specificity wins.
How is the total score calculated?
The score combines all four categories: (inline x 1000) + (ID x 100) + (class/attribute x 10) + (element x 1). This gives you a quick numerical comparison.
Does :not() affect specificity?
Yes. The :not() pseudo-class itself does not add specificity, but the selector inside the parentheses does. For example, :not(#id) contributes an ID-level specificity.
Related CSS Tools
CSS Beautifier
Format and beautify CSS code
Try it
CSS to SCSS
Convert CSS to SCSS/Sass
Try it
CSS to Tailwind
Convert CSS to Tailwind classes
Try it
CSS Grid Generator
Visual CSS Grid layout builder
Try it
CSS Flexbox Generator
Visual Flexbox layout builder
Try it
Border Radius Generator
Visual border-radius editor
Try it
Blog
Latest from Our Blog
How to Choose a Hash Algorithm for Data Security
A practical decision guide to choosing the right hash algorithm: MD5, SHA-1, SHA-2, SHA-3, bcrypt, argon2, PBKDF2, and SRI, with comparisons and clear recommendations.
Aug 08, 2026
CSS vs Tailwind CSS: Which One Should You Use?
A thorough, practical comparison of hand-written CSS and Tailwind CSS: learning curve, maintainability, performance, team workflows, and when each approach wins.
Aug 08, 2026
How to Optimize Core Web Vitals for Your Website
Learn practical, step-by-step techniques to improve LCP, INP, and CLS on your website. A developer-focused guide with real measurements and fixes.
Aug 08, 2026
How to Use Base64 Encoding in Real Projects
Learn practical, production-ready ways to use Base64 encoding: data URLs for images, JWT payloads, API tokens, and email attachments, with real code examples.
Aug 08, 2026
AES Encryption Explained: How It Works and Why It Matters
Learn how AES encryption works, the differences between AES-128, AES-192, and AES-256, and how to encrypt and decrypt data online.
Jun 23, 2026