A CSS noise texture is a visual grain effect created using SVG's <feTurbulence> filter, embedded directly in a background-image as a data URL. It adds subtle organic texture to backgrounds without requiring external image files. This technique is widely used in modern web design to create depth, emulate film grain, paper textures, or add a tactile feel to digital interfaces.

Simply copy the CSS output and paste it into any CSS rule. The code includes both the background-color and the background-image with the SVG data URL. You can apply it to body, div, section, or any HTML element. The noise texture tiles seamlessly by default. You can also extract just the background-image property if you already have a background color set.

Fractal Noise produces smoother, cloud-like undulating patterns with softer transitions — ideal for subtle paper textures and organic backgrounds. Turbulence generates sharper, more chaotic grain resembling TV static or film grain — perfect for gritty, high-contrast noise effects. Both are useful; the choice depends on the aesthetic you're aiming for.

Base frequency determines the granularity of the noise. Lower values (0.1–0.4) produce larger, blotchier grain spots — great for bold textures. Higher values (0.8–2.5) create finer, sand-like grain — ideal for subtle polish. The default of 0.65 provides a balanced mid-frequency grain that works well for most use cases. Combined with the 256×256 tile size, this gives you precise control over perceived particle size.

SVG feTurbulence is rendered by the browser's compositing engine and is generally lightweight, especially for static backgrounds. However, high numOctaves values (5–6) combined with large coverage areas can impact rendering performance on low-end mobile devices. For best results, stick to 2–4 octaves for production sites. The filter runs once during paint and doesn't continuously re-render (unlike CSS animations), so it's quite efficient for static backgrounds.

The feTurbulence SVG filter is supported in all modern browsers: Chrome 5+, Firefox 4+, Safari 6+, Edge 12+, and Opera 11.5+. It also works in mobile browsers including iOS Safari and Android Chrome. The data URL encoding used in the CSS output is universally compatible. If a very old browser doesn't support it, the background color will still display as a graceful fallback.

While the SVG data URL itself is static, you can create a dynamic grain effect by using CSS @keyframes with transform: translate() on a pseudo-element that has the noise background, or by generating multiple SVG variations with different seeds and cross-fading them. However, animated noise can be GPU-intensive. For most use cases, a static noise texture provides the desired aesthetic without performance concerns.

SVG noise textures are resolution-independent (they look sharp at any zoom level), extremely small in file size (typically under 500 bytes as a data URL), require no extra HTTP requests (inline in CSS), and are fully customizable via parameters without needing image editing software. In contrast, PNG textures need to be carefully optimized, can look blurry on high-DPI screens, and require manual regeneration if you want to change the grain intensity or color.