Three SVG squares. All three are 1 inch square.
The red is 96 DPI.
The blue is 72 DPI.
The green is 1234 DPI.
DPI/PPI doesn't matter much if the width and height are specified in physical units. Especially so if the content of the SVG is all vector.
![](data:image/svg+xml;utf8,
<svg xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink"
version="1.1"
width="1in" height="1in" viewBox="0 0 96 96">
<rect width="96" height="96" fill="red"/>
</svg>)
![](data:image/svg+xml;utf8,
<svg xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink"
version="1.1"
width="1in" height="1in" viewBox="0 0 72 72">
<rect width="72" height="72" fill="blue"/>
</svg>)
![](data:image/svg+xml;utf8,
<svg xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink"
version="1.1"
width="1in" height="1in" viewBox="0 0 1234 1234">
<rect width="1234" height="1234" fill="green"/>
</svg>)