Answers for "image at the center in bootstrap"

bootstrap 4 center image

/* used mx-auto d-block */

<img class="mx-auto d-block" src="https://www.w3schools.com/bootstrap4/paris.jpg" alt="https://www.w3schools.com/bootstrap4/paris.jpg"/>

bootstrap Aligning images

Align images with the helper float classes or text alignment classes.
block-level images can be centered using the .mx-auto margin utility class.

<img src="..." class="rounded float-left" alt="...">
<img src="..." class="rounded float-right" alt="...">
<img src="..." class="rounded mx-auto d-block" alt="...">