diff --git a/addons/website/static/src/builder/plugins/image/image_size_tag.js b/addons/website/static/src/builder/plugins/image/image_size_tag.js
new file mode 100644
index 0000000000000..42407bc40748b
--- /dev/null
+++ b/addons/website/static/src/builder/plugins/image/image_size_tag.js
@@ -0,0 +1,20 @@
+import { Component, useState } from "@odoo/owl";
+import { useDomState } from "@html_builder/core/utils";
+import { loadImageDataURL, getImageSizeFromCache } from "@html_editor/utils/image_processing";
+import { KeepLast } from "@web/core/utils/concurrency";
+
+export class ImageSizeTag extends Component {
+    static template = "website.ImageSizeTag";
+    setup() {
+        this.keepLast = new KeepLast();
+        this.state = useState({ size: 0 });
+        useDomState((imageEl) => this.updateImageSize(imageEl));
+        this.updateImageSize(this.env.getEditingElement());
+    }
+
+    async updateImageSize(imageEl) {
+        const src = imageEl.src;
+        await this.keepLast.add(loadImageDataURL(src));
+        this.state.size = Math.round((getImageSizeFromCache(src) / 1024) * 10) / 10;
+    }
+}
diff --git a/addons/website/static/src/builder/plugins/image/image_size_tag.xml b/addons/website/static/src/builder/plugins/image/image_size_tag.xml
new file mode 100644
index 0000000000000..6c975a5d1795b
--- /dev/null
+++ b/addons/website/static/src/builder/plugins/image/image_size_tag.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<templates xml:space="preserve">
+    <t t-name="website.ImageSizeTag">
+        <span class="badge text-bg-dark" title="Size"><t t-out="state.size"/> kB</span>
+    </t>
+</templates>
diff --git a/addons/website/static/src/builder/plugins/image/image_tool_option_plugin.js b/addons/website/static/src/builder/plugins/image/image_tool_option_plugin.js
index 9a04043531593..0368bd1ba6d93 100644
--- a/addons/website/static/src/builder/plugins/image/image_tool_option_plugin.js
+++ b/addons/website/static/src/builder/plugins/image/image_tool_option_plugin.js
@@ -1,4 +1,8 @@
-import { cropperDataFieldsWithAspectRatio, isGif, loadImage } from "@html_editor/utils/image_processing";
+import {
+    cropperDataFieldsWithAspectRatio,
+    isGif,
+    loadImage,
+} from "@html_editor/utils/image_processing";
 import { registry } from "@web/core/registry";
 import { Plugin } from "@html_editor/plugin";
 import { ImageToolOption } from "./image_tool_option";
@@ -11,6 +15,7 @@ import {
 } from "@html_builder/utils/option_sequence";
 import { ReplaceMediaOption, searchSupportedParentLinkEl } from "./replace_media_option";
 import { computeMaxDisplayWidth } from "./image_format_option";
+import { ImageSizeTag } from "./image_size_tag";
 
 export const REPLACE_MEDIA_SELECTOR = "img, .media_iframe_video, span.fa, i.fa";
 export const REPLACE_MEDIA_EXCLUDE =
@@ -28,6 +33,10 @@ class ImageToolOptionPlugin extends Plugin {
     ];
     static shared = ["canHaveHoverEffect"];
     resources = {
+        builder_header_middle_buttons: {
+            Component: ImageSizeTag,
+            selector: "img",
+        },
         builder_options: [
             withSequence(REPLACE_MEDIA, {
                 OptionComponent: ReplaceMediaOption,
@@ -49,32 +58,45 @@ class ImageToolOptionPlugin extends Plugin {
         on_media_dialog_saved_handlers: async (elements, { node }) => {
             for (const image of elements) {
                 if (image && image.tagName === "IMG") {
-                    const updateImageAttributes = await this.dependencies.imagePostProcess.processImage({
-                        img: image,
-                        newDataset: {
-                            formatMimetype: "image/webp",
-                        },
-                        // TODO Using a callback is currently needed to avoid
-                        // the extra RPC that would occur if loadImageInfo was
-                        // called before processImage as well. This flow can be
-                        // simplified if image infos are somehow cached.
-                        onImageInfoLoaded: async (dataset) => {
-                            if (!dataset.originalSrc || !dataset.originalId) {
-                                return true;
-                            }
-                            const original = await loadImage(dataset.originalSrc);
-                            const maxWidth = dataset.width ? image.naturalWidth : original.naturalWidth;
-                            const optimizedWidth = Math.min(maxWidth, computeMaxDisplayWidth(node || this.editable));
-                            if (!["image/gif", "image/svg+xml"].includes(dataset.mimetypeBeforeConversion)) {
-                                // Convert to recommended format and width.
-                                dataset.resizeWidth = optimizedWidth;
-                            } else if (dataset.shape && dataset.mimetypeBeforeConversion !== "image/gif") {
-                                dataset.resizeWidth = optimizedWidth;
-                            } else {
-                                return true;
-                            }
-                        },
-                    });
+                    const updateImageAttributes =
+                        await this.dependencies.imagePostProcess.processImage({
+                            img: image,
+                            newDataset: {
+                                formatMimetype: "image/webp",
+                            },
+                            // TODO Using a callback is currently needed to avoid
+                            // the extra RPC that would occur if loadImageInfo was
+                            // called before processImage as well. This flow can be
+                            // simplified if image infos are somehow cached.
+                            onImageInfoLoaded: async (dataset) => {
+                                if (!dataset.originalSrc || !dataset.originalId) {
+                                    return true;
+                                }
+                                const original = await loadImage(dataset.originalSrc);
+                                const maxWidth = dataset.width
+                                    ? image.naturalWidth
+                                    : original.naturalWidth;
+                                const optimizedWidth = Math.min(
+                                    maxWidth,
+                                    computeMaxDisplayWidth(node || this.editable)
+                                );
+                                if (
+                                    !["image/gif", "image/svg+xml"].includes(
+                                        dataset.mimetypeBeforeConversion
+                                    )
+                                ) {
+                                    // Convert to recommended format and width.
+                                    dataset.resizeWidth = optimizedWidth;
+                                } else if (
+                                    dataset.shape &&
+                                    dataset.mimetypeBeforeConversion !== "image/gif"
+                                ) {
+                                    dataset.resizeWidth = optimizedWidth;
+                                } else {
+                                    return true;
+                                }
+                            },
+                        });
                     updateImageAttributes();
                 }
             }
@@ -91,7 +113,10 @@ class ImageToolOptionPlugin extends Plugin {
                             onClose: resolve,
                             onSave: async (newDataset) => {
                                 resolve(
-                                    this.dependencies.imagePostProcess.processImage({ img, newDataset })
+                                    this.dependencies.imagePostProcess.processImage({
+                                        img,
+                                        newDataset,
+                                    })
                                 );
                             },
                         });