CSS Triangle Generator
Generate pure CSS triangle code with custom directions and pixel dimensions using solid border styling.
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The CSS Triangle Generator produces CSS rules for geometric triangles created with pure border styles. Web developers use border-based shapes to construct lightweight directional markers without loading external images or font glyphs. This generator calculates proportional border widths for eight supported orientations, including cardinal headings like up, down, left, and right, along with corner angles such as top-left, top-right, bottom-left, and bottom-right. When you provide a numeric size value, the tool computes proportional pixel dimensions for each border side using internal arithmetic. The resulting snippet sets the container width and height to zero, specifies a solid border style, and assigns transparent border colors alongside the calculated border widths. Because layout needs vary, adjusting the size updates the height and base proportions across all border segments. You can paste the generated CSS rules into your stylesheet and adjust border colors to match custom tooltips, dropdown carets, indicators, or UI callouts.
Instructions
- Select or enter an orientation such as up, down, left, right, top-left, top-right, bottom-left, or bottom-right.
- Enter a numeric size value to determine the triangle dimensions in pixels.
- Optionally enter a reference color code in the color field.
- Run the generator to view the formatted border-based CSS output.
- Copy the CSS rules into your project stylesheet and apply your desired visible color to the active border side.
Examples
- Setting direction to down with a size of 30 produces CSS code with zero dimensions, solid styling, and calculated pixel border widths arranged for a downward arrow.
- Setting direction to top-right with a size of 40 creates a CSS snippet configured with corner border widths suitable for a diagonal triangle.
FAQ
Which directions does the CSS triangle generator support?
The generator includes specific border patterns for up, down, left, right, top-left, top-right, bottom-left, and bottom-right. If you enter an unrecognized orientation, the output applies the upward border pattern as a fallback.
How does changing the size value modify the CSS?
The numeric size is divided and formatted through internal calculations to set proportional pixel widths across the top, right, bottom, and left border properties.
Why does the output contain transparent border colors?
Pure CSS triangles rely on transparent borders on opposing sides to shape the angle. You can set the visible border side to your chosen color directly in your stylesheet.