CSS Triangle Generator Generate CSS triangles using the border technique with direction and color controls.
CSS Triangle Generator
Generate CSS triangles using the border technique with direction and color controls.
Choose direction
Select which direction the triangle should point: up, down, left, or right.
Customize size and color
Adjust the triangle size and pick your desired color.
Copy the CSS
Preview the triangle and copy the border-based CSS code.
What Is CSS Triangle Generator?
The CSS Triangle Generator creates triangles using the CSS border technique, one of the most clever tricks in CSS. By setting an element's width and height to zero and using transparent borders on three sides with a colored border on one side, a triangle shape is formed. This tool lets you choose the triangle direction (up, down, left, right), adjust its size, and pick any color. The generated CSS is lightweight and requires no images or SVG. CSS triangles are commonly used for tooltip arrows, dropdown indicators, breadcrumb separators, and decorative design elements. The preview shows the triangle in real-time, and the code is ready to copy into your stylesheet.
Why Use CSS Triangle Generator?
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No images needed—pure CSS border technique
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Four direction options with customizable size
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Lightweight and performant alternative to image-based arrows
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Instant preview and one-click code copy
Common Use Cases
Tooltip Arrows
Create the arrow pointer for CSS tooltips and popovers.
Dropdown Indicators
Add triangle indicators to dropdown menus and selectors.
Breadcrumb Separators
Use triangles as visual separators in breadcrumb navigation.
Decorative Elements
Place geometric shapes in section dividers and design accents.
Technical Guide
The CSS triangle technique exploits how borders meet at element corners. For example, border-bottom: 50px solid blue with transparent left and right borders creates an upward-pointing triangle. The triangle size is controlled by the border width values. For equilateral triangles, all border widths should be equal. For isosceles triangles, the colored border can have a different width. This technique can also create right triangles by making only one adjacent border transparent. CSS triangles render crisply at any resolution and are supported in all browsers.
Tips & Best Practices
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1The triangle points opposite to the colored border direction
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2Use matching border widths for equilateral triangles
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3Combine with ::before or ::after pseudo-elements for inline arrows
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4CSS triangles can be rotated with transform for custom angles
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🎨 CSS & DesignFrequently Asked Questions
Q How does the CSS triangle technique work?
Q Can I create triangles pointing at custom angles?
Q Are CSS triangles responsive?
Q Can I create other shapes with borders?
Q Is there a modern alternative to border triangles?
About This Tool
CSS Triangle Generator is a free online tool by FreeToolkit.ai. All processing happens directly in your browser — your data never leaves your device. No registration or installation required.