diff --git a/pure_php/youtube_acl_convert.php b/pure_php/youtube_acl_convert.php
new file mode 100644
index 0000000..2f07730
--- /dev/null
+++ b/pure_php/youtube_acl_convert.php
@@ -0,0 +1,51 @@
+<?php
+
+/**
+ * $ php youtube_acl_trans.php attendees.csv yt-attendees.json
+ */
+
+
+$file = $argv[1];
+$target = $argv[2];
+if (!file_exists($file)) {
+    echo "File not found";
+    die();
+}
+$data = [];
+$producionData = file_exists($target) ? json_decode(file_get_contents($target), true) : [];
+
+$f = fopen($file, 'r');
+$firstLine = true;
+
+$accessMail = array();
+$invalidMail = array();
+
+while (($row = fgets($f)) !== false) {
+    if ($firstLine) {
+        $firstLine = false;
+        continue;
+    }
+    $row = trim($row);
+    $results = explode(",", $row);
+    list($account, $domain) = explode("@", $results[0]);
+    if ($domain != "gmail.com") {
+        // var_dump($domain);
+        $output = shell_exec("dig +short MX $domain");
+        if (preg_match('/(google)/', $output) || preg_match('/(GOOGLE)/', $output)) {
+            $accessMail[] = $results[0];
+        } else {
+            $invalidMail[] = $results[0];
+        }
+    } else {
+        $accessMail[] = $results[0];
+    }
+}
+// 正確信箱
+var_dump("correct: " . count($accessMail));
+// 錯誤信箱
+var_dump("incorrect: " . count($invalidMail));
+// 錯誤率
+var_dump("incorrect rate: " . count($invalidMail) / (count($accessMail) + count($invalidMail)));
+
+file_put_contents(str_replace('.json', '-invalid.json', $target), json_encode(array_values($invalidMail), JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES));
+file_put_contents($target, json_encode(array_values($accessMail), JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES));