diff --git a/Dotnet/AppApi/AppApi.cs b/Dotnet/AppApi/AppApi.cs
index 2e002f41..04aa098f 100644
--- a/Dotnet/AppApi/AppApi.cs
+++ b/Dotnet/AppApi/AppApi.cs
@@ -60,6 +60,65 @@ namespace VRCX
             }
         }
 
+        public string ResizeImageToFitLimits(string base64data)
+        {
+            return Convert.ToBase64String(ResizeImageToFitLimits(Convert.FromBase64String(base64data)));
+        }
+
+        public byte[] ResizeImageToFitLimits(byte[] imageData, int maxWidth = 2000, int maxHeight = 2000, long maxSize = 10_000_000)
+        {
+            using var fileMemoryStream = new MemoryStream(imageData);
+            System.Drawing.Bitmap image = new System.Drawing.Bitmap(fileMemoryStream);
+            if (image.Width > maxWidth)
+            {
+                var sizingFactor = image.Width / (double)maxWidth;
+                int newHeight = (int)Math.Round(image.Height / sizingFactor);
+                image = new System.Drawing.Bitmap(image, maxWidth, newHeight);
+            }
+            if (image.Height > maxHeight)
+            {
+                var sizingFactor = image.Height / (double)maxHeight;
+                int newWidth = (int)Math.Round(image.Width / sizingFactor);
+                image = new System.Drawing.Bitmap(image, newWidth, maxHeight);
+            }
+
+            void saveToFileToUpload()
+            {
+                using var imageSaveMemoryStream = new MemoryStream();
+                image.Save(imageSaveMemoryStream, System.Drawing.Imaging.ImageFormat.Png);
+                imageData = imageSaveMemoryStream.ToArray();
+            }
+
+            saveToFileToUpload();
+
+            for (int i = 0; i < 250 && imageData.Length > maxSize; i++)
+            {
+                saveToFileToUpload();
+                if (imageData.Length < maxSize)
+                    break;
+                int newWidth = image.Width;
+                int newHeight = image.Height;
+                if (image.Width > image.Height)
+                {
+                    newWidth = image.Width - 25;
+                    newHeight = (int)Math.Round(image.Height / (image.Width / (double)newWidth));
+                }
+                else
+                {
+                    newHeight = image.Height - 25;
+                    newWidth = (int)Math.Round(image.Width / (image.Height / (double)newHeight));
+                }
+                image = new System.Drawing.Bitmap(image, newWidth, newHeight);
+            }
+
+            if (imageData.Length > maxSize)
+            {
+                throw new Exception("Failed to get image into target filesize.");
+            }
+
+            return imageData;
+        }
+
         /// <summary>
         /// Computes the signature of the file represented by the specified base64-encoded string using the librsync library.
         /// </summary>
diff --git a/Dotnet/WebApi.cs b/Dotnet/WebApi.cs
index e627d32c..b4f6360a 100644
--- a/Dotnet/WebApi.cs
+++ b/Dotnet/WebApi.cs
@@ -217,7 +217,8 @@ namespace VRCX
                 }
             }
             var imageData = options["imageData"] as string;
-            byte[] fileToUpload = Convert.FromBase64CharArray(imageData.ToCharArray(), 0, imageData.Length);
+            byte[] fileToUpload = AppApi.Instance.ResizeImageToFitLimits(Convert.FromBase64String(imageData));
+
             string fileFormKey = "file";
             string fileName = "blob";
             string fileMimeType = "image/png";
diff --git a/html/src/app.js b/html/src/app.js
index bef3057e..456fb069 100644
--- a/html/src/app.js
+++ b/html/src/app.js
@@ -21598,8 +21598,8 @@ speechSynthesis.getVoices();
         if (!files.length) {
             return;
         }
-        if (files[0].size >= 10000000) {
-            // 10MB
+        if (files[0].size >= 100000000) {
+            // 100MB
             $app.$message({
                 message: 'File size too large',
                 type: 'error'
@@ -21665,8 +21665,8 @@ speechSynthesis.getVoices();
         if (!files.length) {
             return;
         }
-        if (files[0].size >= 10000000) {
-            // 10MB
+        if (files[0].size >= 100000000) {
+            // 100MB
             $app.$message({
                 message: 'File size too large',
                 type: 'error'
@@ -21674,7 +21674,7 @@ speechSynthesis.getVoices();
             this.clearInviteImageUpload();
             return;
         }
-        if (!files[0].type.match(/image.png/)) {
+        if (!files[0].type.match(/image.*/)) {
             $app.$message({
                 message: "File isn't a png",
                 type: 'error'
@@ -22679,6 +22679,11 @@ speechSynthesis.getVoices();
         return response;
     };
 
+    $app.methods.resizeImageToFitLimits = async function (file) {
+        var response = await AppApi.ResizeImageToFitLimits(file);
+        return response;
+    };
+
     $app.methods.genSig = async function (file) {
         var response = await AppApi.SignFile(file);
         return response;
@@ -22706,8 +22711,8 @@ speechSynthesis.getVoices();
             clearFile();
             return;
         }
-        if (files[0].size >= 10000000) {
-            // 10MB
+        if (files[0].size >= 100000000) {
+            // 100MB
             $app.$message({
                 message: 'File size too large',
                 type: 'error'
@@ -22715,7 +22720,7 @@ speechSynthesis.getVoices();
             clearFile();
             return;
         }
-        if (!files[0].type.match(/image.png/)) {
+        if (!files[0].type.match(/image.*/)) {
             $app.$message({
                 message: "File isn't a png",
                 type: 'error'
@@ -22727,7 +22732,8 @@ speechSynthesis.getVoices();
         this.changeAvatarImageDialogLoading = true;
         var r = new FileReader();
         r.onload = async function (file) {
-            var base64File = btoa(r.result);
+            var base64File = await $app.resizeImageToFitLimits(btoa(r.result));
+            // 10MB
             var fileMd5 = await $app.genMd5(base64File);
             var fileSizeInBytes = parseInt(file.total, 10);
             var base64SignatureFile = await $app.genSig(base64File);
@@ -23041,8 +23047,8 @@ speechSynthesis.getVoices();
             clearFile();
             return;
         }
-        if (files[0].size >= 10000000) {
-            // 10MB
+        if (files[0].size >= 100000000) {
+            // 100MB
             $app.$message({
                 message: 'File size too large',
                 type: 'error'
@@ -23050,7 +23056,7 @@ speechSynthesis.getVoices();
             clearFile();
             return;
         }
-        if (!files[0].type.match(/image.png/)) {
+        if (!files[0].type.match(/image.*/)) {
             $app.$message({
                 message: "File isn't a png",
                 type: 'error'
@@ -23062,7 +23068,8 @@ speechSynthesis.getVoices();
         this.changeWorldImageDialogLoading = true;
         var r = new FileReader();
         r.onload = async function (file) {
-            var base64File = btoa(r.result);
+            var base64File = await $app.resizeImageToFitLimits(btoa(r.result));
+            // 10MB
             var fileMd5 = await $app.genMd5(base64File);
             var fileSizeInBytes = parseInt(file.total, 10);
             var base64SignatureFile = await $app.genSig(base64File);
@@ -25073,8 +25080,8 @@ speechSynthesis.getVoices();
         if (!files.length) {
             return;
         }
-        if (files[0].size >= 10000000) {
-            // 10MB
+        if (files[0].size >= 100000000) {
+            // 100MB
             $app.$message({
                 message: 'File size too large',
                 type: 'error'
@@ -25184,8 +25191,8 @@ speechSynthesis.getVoices();
         if (!files.length) {
             return;
         }
-        if (files[0].size >= 10000000) {
-            // 10MB
+        if (files[0].size >= 100000000) {
+            // 100MB
             $app.$message({
                 message: 'File size too large',
                 type: 'error'
diff --git a/html/src/index.pug b/html/src/index.pug
index ae38d12e..4a599af4 100644
--- a/html/src/index.pug
+++ b/html/src/index.pug
@@ -2428,7 +2428,7 @@ html
             //- dialog: Change avatar image
             el-dialog.x-dialog(:before-close="beforeDialogClose" @mousedown.native="dialogMouseDown" @mouseup.native="dialogMouseUp" ref="changeAvatarImageDialog" :visible.sync="changeAvatarImageDialogVisible" :title="$t('dialog.change_content_image.avatar')" width="850px")
                 div(v-if="changeAvatarImageDialogVisible" v-loading="changeAvatarImageDialogLoading")
-                    input(type="file" accept="image/*" @change="onFileChangeAvatarImage" id="AvatarImageUploadButton" style="display:none")
+                    input(type="file" accept="image/png,image/jpg,image/jpeg,image/webp,image/bmp,image/gif" @change="onFileChangeAvatarImage" id="AvatarImageUploadButton" style="display:none")
                     span {{ $t('dialog.change_content_image.description') }}
                     br
                     el-button-group(style="padding-bottom:10px;padding-top:10px")
@@ -2443,7 +2443,7 @@ html
             //- dialog: Change world image
             el-dialog.x-dialog(:before-close="beforeDialogClose" @mousedown.native="dialogMouseDown" @mouseup.native="dialogMouseUp" ref="changeWorldImageDialog" :visible.sync="changeWorldImageDialogVisible" :title="$t('dialog.change_content_image.world')" width="850px")
                 div(v-if="changeWorldImageDialogVisible" v-loading="changeWorldImageDialogLoading")
-                    input(type="file" accept="image/*" @change="onFileChangeWorldImage" id="WorldImageUploadButton" style="display:none")
+                    input(type="file" accept="image/png,image/jpg,image/jpeg,image/webp,image/bmp,image/gif" @change="onFileChangeWorldImage" id="WorldImageUploadButton" style="display:none")
                     span {{ $t('dialog.change_content_image.description') }}
                     br
                     el-button-group(style="padding-bottom:10px;padding-top:10px")
@@ -2472,7 +2472,7 @@ html
                     el-tab-pane(v-if="galleryDialogVisible" v-loading="galleryDialogGalleryLoading")
                         span(slot="label") {{ $t('dialog.gallery_icons.gallery') }}
                             span(style="color:#909399;font-size:12px;margin-left:5px") {{ galleryTable.length }}/64
-                        input(type="file" accept="image/*" @change="onFileChangeGallery" id="GalleryUploadButton" style="display:none")
+                        input(type="file" accept="image/png,image/jpg,image/jpeg,image/webp,image/bmp,image/gif" @change="onFileChangeGallery" id="GalleryUploadButton" style="display:none")
                         el-button-group
                             el-button(type="default" size="small" @click="refreshGalleryTable" icon="el-icon-refresh") {{ $t('dialog.gallery_icons.refresh') }}
                             el-button(type="default" size="small" @click="displayGalleryUpload" icon="el-icon-upload2" :disabled="!API.currentUser.$isVRCPlus") {{ $t('dialog.gallery_icons.upload') }}
@@ -2487,7 +2487,7 @@ html
                     el-tab-pane(v-if="galleryDialogVisible" v-loading="galleryDialogIconsLoading")
                         span(slot="label") {{ $t('dialog.gallery_icons.icons') }}
                             span(style="color:#909399;font-size:12px;margin-left:5px") {{ VRCPlusIconsTable.length }}/64
-                        input(type="file" accept="image/*" @change="onFileChangeVRCPlusIcon" id="VRCPlusIconUploadButton" style="display:none")
+                        input(type="file" accept="image/png,image/jpg,image/jpeg,image/webp,image/bmp,image/gif" @change="onFileChangeVRCPlusIcon" id="VRCPlusIconUploadButton" style="display:none")
                         el-button-group
                             el-button(type="default" size="small" @click="refreshVRCPlusIconsTable" icon="el-icon-refresh") {{ $t('dialog.gallery_icons.refresh') }}
                             el-button(type="default" size="small" @click="displayVRCPlusIconUpload" icon="el-icon-upload2" :disabled="!API.currentUser.$isVRCPlus") {{ $t('dialog.gallery_icons.upload') }}
@@ -2502,7 +2502,7 @@ html
                     el-tab-pane(v-if="galleryDialogVisible" v-loading="galleryDialogIconsLoading")
                         span(slot="label") {{ $t('dialog.gallery_icons.emojis') }}
                             span(style="color:#909399;font-size:12px;margin-left:5px") {{ emojiTable.length }}/9
-                        input(type="file" accept="image/*" @change="onFileChangeEmoji" id="EmojiUploadButton" style="display:none")
+                        input(type="file" accept="image/png,image/jpg,image/jpeg,image/webp,image/bmp,image/gif" @change="onFileChangeEmoji" id="EmojiUploadButton" style="display:none")
                         el-button-group(style="margin-right:10px")
                             el-button(type="default" size="small" @click="refreshEmojiTable" icon="el-icon-refresh") {{ $t('dialog.gallery_icons.refresh') }}
                             el-button(type="default" size="small" @click="displayEmojiUpload" icon="el-icon-upload2" :disabled="!API.currentUser.$isVRCPlus") {{ $t('dialog.gallery_icons.upload') }}
@@ -2977,7 +2977,7 @@ html
                     span(slot="label") {{ $t('dialog.gallery_select.gallery') }}
                     span(style="color:#909399;font-size:12px;margin-left:5px") {{ galleryTable.length }}/64
                     br
-                    input(type="file" accept="image/*" @change="onFileChangeGallery" id="GalleryUploadButton" style="display:none")
+                    input(type="file" accept="image/png,image/jpg,image/jpeg,image/webp,image/bmp,image/gif" @change="onFileChangeGallery" id="GalleryUploadButton" style="display:none")
                     el-button-group
                         el-button(type="default" size="small" @click="selectImageGallerySelect('', '')" icon="el-icon-close") {{ $t('dialog.gallery_select.none') }}
                         el-button(type="default" size="small" @click="refreshGalleryTable" icon="el-icon-refresh") {{ $t('dialog.gallery_select.refresh') }}