Bootstrap Breakpoint Tester

The Bootstrap Breakpoint Tester generates a complete, self-contained HTML page with a live breakpoint indicator and configurable grid demo so you can instantly see how Bootstrap 5 responds across all six breakpoints (xs, sm, md, lg, xl, xxl). It's built for frontend developers, UI designers, and anyone integrating Bootstrap into a project who needs to verify responsive behaviour without spinning up a local dev environment.

Configuration

Content

Page Title

Page Subtitle

Number of Demo Cards

Card Title Prefix

Card Body Text

Navbar Brand Name

Navbar Links (one per line)

Footer Text

Layout

Columns per Row (md+)

Container Type

Gutter Size

Include Sample NavbarInclude Sample Footer

Design

Accent / Brand Color

Card Border Radius (px)

Breakpoint Badge Background

Dark Mode

How to Use

1. Configure the number of grid columns, gutter size, and container type you want to test. 2. Adjust the accent color, border-radius, and optional content visibility settings to match your project's design tokens. 3. Preview the rendered output, the live badge at the top of the output always shows the current active breakpoint. 4. Copy or download the generated HTML and paste it directly into your project or open it standalone in any browser.

Why Use This Tool?

Manually writing breakpoint test scaffolding from scratch wastes 20–30 minutes every time you start a new project or debug a layout regression. This tool produces a zero-dependency, production-ready HTML file that requires only the Bootstrap 5 CDN, no Node, no Webpack, no PostCSS. It's particularly useful when handing off responsive specs to a client or QA tester who needs a standalone reference file.

Frequently Asked Questions

What is the Bootstrap Breakpoint Tester?

It's a free online tool that generates a fully functional Bootstrap 5 HTML page containing a real-time breakpoint indicator badge and a configurable responsive grid demo, so you can observe exactly how Bootstrap's breakpoint system behaves in any browser.

How does the live breakpoint indicator work in the generated HTML?

The output uses Bootstrap's built-in display utility classes (d-block, d-sm-none, d-md-none, etc.) to show a labelled badge that reveals only on its matching breakpoint. Because it relies purely on Bootstrap's CSS media queries, not JavaScript, it works identically in every modern browser and accurately reflects the same thresholds Bootstrap uses internally: xs (<576px), sm (≥576px), md (≥768px), lg (≥992px), xl (≥1200px), xxl (≥1400px).

Is it free?

Yes, the Bootstrap Breakpoint Tester is completely free with no signup required. Built by the CanvasBuilder.co team.