diff --git a/app/src/full/java/com/topjohnwu/magisk/Data.java b/app/src/full/java/com/topjohnwu/magisk/Data.java
index a0d62f05b..cbb8812cc 100644
--- a/app/src/full/java/com/topjohnwu/magisk/Data.java
+++ b/app/src/full/java/com/topjohnwu/magisk/Data.java
@@ -33,6 +33,7 @@ public class Data {
     public static int remoteMagiskVersionCode = -1;
     public static String magiskLink;
     public static String magiskNoteLink;
+    public static String magiskMD5;
     public static String remoteManagerVersionString;
     public static int remoteManagerVersionCode = -1;
     public static String managerLink;
diff --git a/app/src/full/java/com/topjohnwu/magisk/asyncs/CheckUpdates.java b/app/src/full/java/com/topjohnwu/magisk/asyncs/CheckUpdates.java
index 98afc6c59..9dbda9539 100644
--- a/app/src/full/java/com/topjohnwu/magisk/asyncs/CheckUpdates.java
+++ b/app/src/full/java/com/topjohnwu/magisk/asyncs/CheckUpdates.java
@@ -68,6 +68,7 @@ public class CheckUpdates {
         Data.remoteMagiskVersionCode = getInt(magisk, "versionCode", -1);
         Data.magiskLink = getString(magisk, "link", null);
         Data.magiskNoteLink = getString(magisk, "note", null);
+        Data.magiskMD5 = getString(magisk, "md5", null);
 
         JSONObject manager = getJson(json, "app");
         Data.remoteManagerVersionString = getString(manager, "version", null);
diff --git a/app/src/full/java/com/topjohnwu/magisk/asyncs/InstallMagisk.java b/app/src/full/java/com/topjohnwu/magisk/asyncs/InstallMagisk.java
index e295229c4..586229628 100644
--- a/app/src/full/java/com/topjohnwu/magisk/asyncs/InstallMagisk.java
+++ b/app/src/full/java/com/topjohnwu/magisk/asyncs/InstallMagisk.java
@@ -35,6 +35,7 @@ import org.kamranzafar.jtar.TarOutputStream;
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
 import java.io.File;
+import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.FilterInputStream;
@@ -136,19 +137,28 @@ public class InstallMagisk extends ParallelTask<Void, Void, Boolean> {
     }
 
     private void extractFiles(String arch) throws IOException {
-        console.add("- Downloading zip");
         String filename = Utils.fmt("Magisk-v%s(%d).zip",
                 Data.remoteMagiskVersionString, Data.remoteMagiskVersionCode);
-        HttpURLConnection conn = WebService.mustRequest(Data.magiskLink, null);
-        BufferedInputStream buf = new BufferedInputStream(new ProgressStream(conn));
-        buf.mark(Integer.MAX_VALUE);
         File zip = new File(Download.EXTERNAL_PATH, filename);
         zip.getParentFile().mkdirs();
-        try (OutputStream out = new FileOutputStream(zip)) {
-            ShellUtils.pump(buf, out);
+        BufferedInputStream buf;
+
+        if (!ShellUtils.checkSum("MD5", zip, Data.magiskMD5)) {
+            console.add("- Downloading zip");
+            HttpURLConnection conn = WebService.mustRequest(Data.magiskLink, null);
+            buf = new BufferedInputStream(new ProgressStream(conn), conn.getContentLength());
+            buf.mark(Integer.MAX_VALUE);
+            try (OutputStream out = new FileOutputStream(zip)) {
+                ShellUtils.pump(buf, out);
+            }
             buf.reset();
+            conn.disconnect();
+        } else {
+            console.add("- Existing zip found");
+            buf = new BufferedInputStream(new FileInputStream(zip), (int) zip.length());
+            buf.mark(Integer.MAX_VALUE);
         }
-        conn.disconnect();
+
         console.add("- Extracting files");
         try (InputStream in = buf) {
             ZipUtils.unzip(in, installDir, arch + "/", true);