diff --git a/src/LLMProviders/brevilabsClient.ts b/src/LLMProviders/brevilabsClient.ts
index 14ebb74c..acc22937 100644
--- a/src/LLMProviders/brevilabsClient.ts
+++ b/src/LLMProviders/brevilabsClient.ts
@@ -3,7 +3,7 @@ import { getDecryptedKey } from "@/encryptionService";
 import { logInfo } from "@/logger";
 import { turnOffPlus, turnOnPlus } from "@/plusUtils";
 import { getSettings } from "@/settings/model";
-import { Buffer } from "buffer";
+import { arrayBufferToBase64 } from "@/utils/base64";
 import { Notice } from "obsidian";
 
 export interface BrocaResponse {
@@ -307,7 +307,7 @@ export class BrevilabsClient {
 
   async pdf4llm(binaryContent: ArrayBuffer): Promise<Pdf4llmResponse> {
     // Convert ArrayBuffer to base64 string
-    const base64Content = Buffer.from(binaryContent).toString("base64");
+    const base64Content = arrayBufferToBase64(binaryContent);
 
     const { data, error } = await this.makeRequest<Pdf4llmResponse>("/pdf4llm", {
       pdf: base64Content,
diff --git a/src/components/Chat.tsx b/src/components/Chat.tsx
index 7ec012c2..f256ee09 100644
--- a/src/components/Chat.tsx
+++ b/src/components/Chat.tsx
@@ -22,8 +22,8 @@ import {
   ABORT_REASON,
   EVENT_NAMES,
   LOADING_MESSAGES,
-  USER_SENDER,
   RESTRICTION_MESSAGES,
+  USER_SENDER,
 } from "@/constants";
 import { AppContext, EventTargetContext } from "@/context";
 import { useChatManager } from "@/hooks/useChatManager";
@@ -36,7 +36,7 @@ import { updateSetting, useSettingsValue } from "@/settings/model";
 import { ChatUIState } from "@/state/ChatUIState";
 import { FileParserManager } from "@/tools/FileParserManager";
 import { err2String, isPlusChain } from "@/utils";
-import { Buffer } from "buffer";
+import { arrayBufferToBase64 } from "@/utils/base64";
 import { Notice, TFile } from "obsidian";
 import React, { useCallback, useContext, useEffect, useMemo, useRef, useState } from "react";
 
@@ -182,7 +182,7 @@ const Chat: React.FC<ChatProps> = ({
       // Add images if present
       for (const image of selectedImages) {
         const imageData = await image.arrayBuffer();
-        const base64Image = Buffer.from(imageData).toString("base64");
+        const base64Image = arrayBufferToBase64(imageData);
         content.push({
           type: "image_url",
           image_url: {
diff --git a/src/imageProcessing/imageProcessor.ts b/src/imageProcessing/imageProcessor.ts
index e480c43d..d47bf2b8 100644
--- a/src/imageProcessing/imageProcessor.ts
+++ b/src/imageProcessing/imageProcessor.ts
@@ -1,5 +1,6 @@
 import { logError } from "@/logger";
 import { safeFetch } from "@/utils";
+import { arrayBufferToBase64 } from "@/utils/base64";
 import { Notice, TFile, Vault } from "obsidian";
 
 export interface ImageContent {
@@ -196,8 +197,7 @@ export class ImageProcessor {
         return null;
       }
 
-      const buffer = Buffer.from(arrayBuffer);
-      const base64 = buffer.toString("base64");
+      const base64 = arrayBufferToBase64(arrayBuffer);
 
       const result = `data:${mimeType};base64,${base64}`;
       return result;
@@ -234,8 +234,7 @@ export class ImageProcessor {
         return null;
       }
 
-      const buffer = Buffer.from(arrayBuffer);
-      const base64 = buffer.toString("base64");
+      const base64 = arrayBufferToBase64(arrayBuffer);
       return `data:${contentType};base64,${base64}`;
     } catch (error) {
       logError("Error converting web image to base64:", error);
@@ -268,8 +267,7 @@ export class ImageProcessor {
         return null;
       }
 
-      const buffer = Buffer.from(arrayBuffer);
-      const base64 = buffer.toString("base64");
+      const base64 = arrayBufferToBase64(arrayBuffer);
 
       const result = `data:${mimeType};base64,${base64}`;
       return result;
diff --git a/src/utils/base64.ts b/src/utils/base64.ts
new file mode 100644
index 00000000..43199459
--- /dev/null
+++ b/src/utils/base64.ts
@@ -0,0 +1,17 @@
+export function arrayBufferToBase64(buffer: ArrayBuffer): string {
+  const bytes = new Uint8Array(buffer);
+  let binary = "";
+  for (let i = 0; i < bytes.byteLength; i++) {
+    binary += String.fromCharCode(bytes[i]);
+  }
+  return (globalThis as any)["btoa"](binary);
+}
+
+export function base64ToArrayBuffer(base64: string): ArrayBuffer {
+  const binaryString = (globalThis as any)["atob"](base64);
+  const bytes = new Uint8Array(binaryString.length);
+  for (let i = 0; i < binaryString.length; i++) {
+    bytes[i] = binaryString.charCodeAt(i);
+  }
+  return bytes.buffer;
+}