diff --git a/config.inc.php b/config.inc.php
index 376bfbe3..949fe96e 100644
--- a/config.inc.php
+++ b/config.inc.php
@@ -194,6 +194,7 @@ $CONF['smtp_sendmail_tls'] = 'NO';
 //     - don't use dovecot:* methods that include the username in the hash - you won't be able to login to PostfixAdmin in this case
 //     - you'll need at least dovecot 2.1 for salted passwords ('doveadm pw' 2.0.x doesn't support the '-t' option)
 //     - dovecot 2.0.0 - 2.0.7 is not supported
+// sha512.b64 - {SHA512-CRYPT.B64} (base64 encoded sha512) (no dovecot dependency; should support migration from md5crypt)
 $CONF['encrypt'] = 'md5crypt';
 
 // In what flavor should courier-authlib style passwords be encrypted?
diff --git a/functions.inc.php b/functions.inc.php
index 457bb94e..4b2f9ac3 100644
--- a/functions.inc.php
+++ b/functions.inc.php
@@ -1232,6 +1232,8 @@ function pacrypt($pw, $pw_db="") {
             return _pacrypt_mysql_encrypt($pw, $pw_db);
         case 'authlib':
             return _pacrypt_authlib($pw, $pw_db);
+        case 'sha512.b64':
+            return _pacrypt_sha512_b64($pw, $pw_db);
     }
 
     if (preg_match("/^dovecot:/", $CONF['encrypt'])) {
@@ -1245,6 +1247,35 @@ function pacrypt($pw, $pw_db="") {
     throw new Exception('unknown/invalid $CONF["encrypt"] setting: ' . $CONF['encrypt']);
 }
 
+/**
+ * @see https://github.com/postfixadmin/postfixadmin/issues/58
+ */
+function _pacrypt_sha512_b64($pw, $pw_db="") {
+    if (!function_exists('random_bytes') || !function_exists('crypt') || !defined('CRYPT_SHA512') || !function_exists('mb_substr')) {
+        throw new Exception("sha512.b64 not supported!");
+    }
+    if (!$pw_db) {
+        $salt = mb_substr(rtrim(base64_encode(random_bytes(16)),'='),0,16,'8bit');
+        return '{SHA512-CRYPT.B64}'.base64_encode(crypt($pw,'$6$'.$salt));
+    } 
+
+
+    $password="#Thepasswordcannotbeverified";
+    if (strncmp($pw_db,'{SHA512-CRYPT.B64}',18)==0) {
+        $dcpwd = base64_decode(mb_substr($pw_db,18,NULL,'8bit'),true);
+        if ($dcpwd !== false && !empty($dcpwd) && strncmp($dcpwd,'$6$',3)==0) {
+            $password = '{SHA512-CRYPT.B64}'.base64_encode(crypt($pw,$dcpwd));
+        }
+    }
+    elseif (strncmp($pw_db,'{MD5-CRYPT}',11)==0) {
+        $dcpwd = mb_substr($pw_db,11,NULL,'8bit');
+        if (!empty($dcpwd) && strncmp($dcpwd,'$1$',3)==0) {
+            $password = '{MD5-CRYPT}'.crypt($pw,$dcpwd);
+        }
+    }
+    return $password;
+}
+
 /**
  * Creates MD5 based crypt formatted password.
  * If salt is not provided we generate one.
diff --git a/tests/PacryptTest.php b/tests/PacryptTest.php
index 24660706..6142439a 100644
--- a/tests/PacryptTest.php
+++ b/tests/PacryptTest.php
@@ -116,4 +116,29 @@ class PaCryptTest extends \PHPUnit\Framework\TestCase {
         // not impossible though.
         $this->assertFalse( strcmp($str1, $str2) == 0 && strcmp($str1, $str3) == 0 );
     }
+
+    public function testSha512B64() {
+        $str1 = _pacrypt_sha512_b64('test', '');
+        $str2 = _pacrypt_sha512_b64('test', '');
+
+        $this->assertNotEmpty($str1);
+        $this->assertNotEmpty($str2);
+        $this->assertNotEquals($str1, $str2); // should have different salts
+
+
+        $actualHash = '{SHA512-CRYPT.B64}JDYkM2NWcFM1WFNlUHl5MzdwSiRZWW80d0FmeWg5MXpxcS4uY3dtYUR1Y1RodTJGTDY1NHpXNUNvRU0wT3hXVFFzZkxIZ1JJSTZmT281OVpDUWJOTTF2L0JXajloME0vVjJNbENNMUdwLg==';
+
+        $check = _pacrypt_sha512_b64('test', $actualHash);
+
+        $this->assertTrue(hash_equals($check, $actualHash));
+
+        $str3 = _pacrypt_sha512_b64('foo', '');
+
+        $this->assertNotEmpty($str3);
+
+        $this->assertFalse(hash_equals('test', $str3));
+
+        $this->assertTrue(hash_equals(_pacrypt_sha512_b64('foo',$str3), $str3));
+
+    }
 }