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CSS Inliner

Transform external or internal CSS rules into inline HTML styles. Essential for maximizing email template compatibility across all clients.

Input HTML and CSS

Provide your HTML and CSS below to inline the styles into the HTML.

What Is the CSS Inliner Tool?

The CSS Inliner is a free online utility that helps you transform external and internal CSS rules into inline HTML styles, essential for email template compatibility across Gmail, Outlook, and other email clients.

The CSS Inliner combines your HTML and CSS, then uses the juice library to apply all style rules directly to each HTML element as inline styles. The result is reformatted with Prettier for readability. This process ensures consistent rendering across email clients that strip external stylesheets.

Key Features

  • Combines external and internal CSS styles into inline HTML attributes
  • Prettier formatting for clean, readable output HTML
  • Support for complex CSS selectors including class and element targeting
  • Preserves existing inline styles while adding computed styles
  • Client-side and server-side processing options
  • One-click copy for email template integration

Why Use This Tool

  • Ensures consistent email rendering across all email clients including Gmail and Outlook
  • Eliminates the need for multiple email versions for different clients
  • Preserves complex CSS selectors by computing and applying final computed styles
  • Produces self-contained HTML that renders correctly without external resources
  • Saves hours of manual inline styling for email template development

Common Use Cases

  • Preparing HTML email templates for marketing campaigns and transactional emails
  • Creating self-contained HTML documents for offline viewing and distribution
  • Ensuring newsletter compatibility across diverse email clients and devices
  • Converting existing websites with external CSS into portable HTML snapshots
  • Building email templates in frameworks that use external CSS during development

Technical Details

This tool uses the juice npm package for CSS inlining combined with Prettier for output formatting. The juice library parses CSS rules and applies them to matching HTML elements by computing the final style for each element and writing it as an inline style attribute. The API runs server-side for reliable processing.


Frequently Asked Questions

Is this tool free to use?

Yes, the CSS Inliner is completely free to use with no signup, registration, or usage limits required.

Is my data sent to a server?

Your data is sent to our server-side API for processing only. It is not stored, logged, or shared with any third parties and is discarded immediately after processing.

What is CSS inlining?

CSS inlining applies styles directly to each HTML element as inline styles, essential for HTML email compatibility since email clients strip external stylesheets.

Why do emails need inlined CSS?

Email clients like Gmail and Outlook strip external and internal stylesheets. Inlined CSS ensures consistent rendering across all clients.

Does inlining increase file size?

Yes, styles are repeated per element, but this trade-off is necessary for email compatibility and consistent rendering.

What library is used?

This tool uses juice for CSS inlining and Prettier for formatting the output.

Can I use this tool offline?

This tool requires a server-side API call, so an internet connection is needed for processing.


Credits & Source

Maintained by Vijay Hardaha. This tool is built with modern web technologies and industry-standard open-source libraries to deliver reliable, high-quality results.


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