The numOctaves attribute defines the number of octaves for the noise function of the <feTurbulence> primitive.

An octave is a noise function defined by its frequency and amplitude. A turbulence is built by accumulating several octaves with increasing frequencies and decreasing amplitudes.
The higher the number of octaves, the more natural the noise looks. Though more octaves also require more calculations, resulting in a negative impact on performance.

Only one element is using this attribute: <feTurbulence>

<svg viewBox="0 0 420 200" xmlns="http://www.w3.org/2000/svg">
  <filter id="noise1" x="0" y="0" width="100%" height="100%">
    <feTurbulence baseFrequency="0.025" numOctaves="1" />
  <filter id="noise2" x="0" y="0" width="100%" height="100%">
    <feTurbulence baseFrequency="0.025" numOctaves="3" />

  <rect x="0" y="0" width="200" height="200" style="filter: url(#noise1);" />
  <rect x="0" y="0" width="200" height="200" style="filter: url(#noise2); transform: translateX(220px);" />

Usage notes

Value <integer>
Default value 1
Animatable Yes
Defines the number of octaves. Negative values are forbidden.


<svg width="200" height="200" viewBox="0 0 220 220"
  <filter id="displacementFilter">
    <feTurbulence baseFrequency="0.05"
        numOctaves="3" result="turbulence"/>
    <feDisplacementMap in2="turbulence" in="SourceGraphic"
        scale="50" xChannelSelector="R" yChannelSelector="G"/>

  <circle cx="100" cy="100" r="100"
      style="filter: url(#displacementFilter)"/>


Browser compatibilityUpdate compatibility data on GitHub

Chrome Edge Firefox Internet Explorer Opera Safari
numOctaves ? ? ? ? ? ?
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
numOctaves ? ? ? ? ? ?

See also

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