diff --git a/packages/backend/src/server/file/send-drive-file.ts b/packages/backend/src/server/file/send-drive-file.ts
index 967df1d57..cefd13a51 100644
--- a/packages/backend/src/server/file/send-drive-file.ts
+++ b/packages/backend/src/server/file/send-drive-file.ts
@@ -11,7 +11,7 @@ import { DriveFiles } from '@/models/index';
 import { InternalStorage } from '@/services/drive/internal-storage';
 import { downloadUrl } from '@/misc/download-url';
 import { detectType } from '@/misc/get-file-info';
-import { convertToJpeg, convertToPng } from '@/services/drive/image-processor';
+import { convertToWebp, convertToPng } from '@/services/drive/image-processor';
 import { GenerateVideoThumbnail } from '@/services/drive/generate-video-thumbnail';
 import { StatusError } from '@/misc/fetch';
 import { FILE_TYPE_BROWSERSAFE } from '@/const';
@@ -65,10 +65,8 @@ export default async function(ctx: Koa.Context) {
 
 				const convertFile = async () => {
 					if (isThumbnail) {
-						if (['image/jpeg', 'image/webp'].includes(mime)) {
-							return await convertToJpeg(path, 498, 280);
-						} else if (['image/png', 'image/svg+xml'].includes(mime)) {
-							return await convertToPng(path, 498, 280);
+						if (['image/jpeg', 'image/webp', 'image/png', 'image/svg+xml'].includes(mime)) {
+							return await convertToWebp(path, 498, 280);
 						} else if (mime.startsWith('video/')) {
 							return await GenerateVideoThumbnail(path);
 						}
diff --git a/packages/backend/src/services/drive/add-file.ts b/packages/backend/src/services/drive/add-file.ts
index 0135ca107..04e9c8dbc 100644
--- a/packages/backend/src/services/drive/add-file.ts
+++ b/packages/backend/src/services/drive/add-file.ts
@@ -194,6 +194,7 @@ export async function generateAlts(path: string, type: string, generateWeb: bool
 		}
 
 		satisfyWebpublic = !!(
+			type !== 'image/svg+xml' &&
 			!(metadata.exif || metadata.iptc || metadata.xmp || metadata.tifftagPhotoshop) &&
 			metadata.width && metadata.width <= 2048 &&
 			metadata.height && metadata.height <= 2048
diff --git a/packages/client/src/scripts/upload.ts b/packages/client/src/scripts/upload.ts
index 06d4e9ddd..af0de3878 100644
--- a/packages/client/src/scripts/upload.ts
+++ b/packages/client/src/scripts/upload.ts
@@ -16,10 +16,10 @@ export const uploads = ref<Uploading[]>([]);
 
 const compressTypeMap = new Map([
 	// [圧縮前の形式, 圧縮後の形式],
-	['image/jpeg', 'image/jpeg'],
-	['image/webp', 'image/jpeg'],
-	['image/png', 'image/png'],
-	['image/svg', 'image/png'],
+	['image/jpeg', 'image/webp'],
+	['image/webp', 'image/webp'],
+	['image/png', 'image/webp'],
+	['image/svg', 'image/webp'],
 ]);
 
 export function uploadFile(file: File, folder?: any, name?: string, keepOriginal: boolean = defaultStore.state.keepOriginalUploading): Promise<Misskey.entities.DriveFile> {