Will beautifying change CSS behavior?

No. Formatting changes whitespace and indentation only when CSS is valid. Semantics are preserved.

Can vendor prefixes be handled?

Yes, beautifier recognizes -webkit-, -moz-, -ms-, -o- prefixes and formats them normally.

Media queries are treated as rule containers and indented consistently with their contents.

Yes, --var-name syntax is supported and formatted like any other property.

The formatter handles standard CSS. For SCSS/LESS-specific syntax (mixins, nesting), use dedicated preprocessor beautifiers.

Yes, all at-rules are preserved and formatted with their nested content.

Web Studio Tools

Format CSS rules for clean, maintainable stylesheets.

CSS Beautifier formats and validates CSS stylesheets with consistent indentation and rule organization.
Detect syntax errors, reformat selectors and properties, and prepare clean CSS for production stylesheets and code review.

Paste CSS into the editor—from snippets to full stylesheets.
The beautifier validates syntax and highlights errors in malformed CSS.
Adjust indentation level if needed and review the formatted output.
Copy or download the beautified CSS for stylesheets, documentation, or version control.

Formatting improves readability but does not optimize bundle size or runtime performance.
Invalid CSS syntax must be corrected before reliable formatting.

Missing semicolon: color: red background: blue breaks the rule. Each declaration must end with ;.
No braces: color: red; outside braces is invalid. All declarations must be inside { }.
Missing colon: color red is invalid; must be color: red.
Invalid units: width: 100 (unitless) succeeds for some properties but fails for sizes. Use px or other explicit units.
Incorrect property names: bgcolor is HTML, not CSS; use background-color.
Selector syntax errors: div.class > p is valid, but div class > p (space instead of dot) fails.
Unclosed comments: /* comment without */ breaks all following CSS.

Rule: A selector followed by declarations in braces. Example: body { color: black; }.
Selector: The element(s) a rule targets. Examples: p, .class, #id, div > p, a:hover.
Declaration: A property-value pair ending with semicolon. Example: color: blue;.
Property: The CSS attribute being set. Example: color, background, margin, display.
Value: The setting for a property. Examples: blue, 16px, center, flex, url(image.png).
Unit: Measurement suffix on numeric values. Examples: px, em, rem, %, vh, etc.
At-rules: Statements starting with @. Examples: @media, @import, @keyframes, @font-face.
Pseudo-class: Adds state to selector. Examples: :hover, :focus, :nth-child(n).
Pseudo-element: Targets parts of element. Examples: ::before, ::after, ::first-line.
Comment: /* comment */. Can span multiple lines. Useful for documenting sections.

Specifications & Standards

Will beautifying change CSS behavior?
No. Formatting changes whitespace and indentation only when CSS is valid. Semantics are preserved.
Can vendor prefixes be handled?
Yes, beautifier recognizes -webkit-, -moz-, -ms-, -o- prefixes and formats them normally.
How are media queries formatted?
Media queries are treated as rule containers and indented consistently with their contents.
Can CSS variables (custom properties) be used?
Yes, --var-name syntax is supported and formatted like any other property.
What if I have SCSS or LESS?
The formatter handles standard CSS. For SCSS/LESS-specific syntax (mixins, nesting), use dedicated preprocessor beautifiers.
Will @import and @media be preserved?
Yes, all at-rules are preserved and formatted with their nested content.

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