To set the background color for the circle SVG element, you can use the fill attribute on the circle element inside the svg tag in HTML.

TL;DR

<!-- Set background color on 'circle' svg element -->
<svg>
  <circle cx="30" cy="30" r="30" fill="red" />
</svg>

For example to set the color red on the circle svg element, let's use the fill attribute and set its value to the string red like this,

<!-- Set background color on 'circle' svg element -->
<svg>
  <circle fill="red" />
</svg>

But this alone wouldn't show anything on the screen as the browser doesn't know where to start drawing the shape. For that, you also have to add other 3 attributes like the cx, cy, and r. To know more about these attributes check out How to create or draw a circle using SVG in HTML?

So at the end it will look like this,

<!-- Set background color on 'circle' svg element 🔥 -->
<svg>
  <circle cx="30" cy="30" r="30" fill="red" />
</svg>

See the above code live in JSBin.

That's all 😃!

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