diff --git a/src/DateCheck.php b/src/DateCheck.php
new file mode 100644
index 0000000..ff59eae
--- /dev/null
+++ b/src/DateCheck.php
@@ -0,0 +1,27 @@
+<?php
+namespace Misuzu;
+
+final class DateCheck {
+    public static function isLeapYear(int $year): bool {
+        return (($year % 4) === 0 && ($year % 100) !== 0)
+            || ($year % 400) === 0;
+    }
+
+    // i realise this implementation is probably horribly naive,
+    //  but for what i need it will Do the Job
+    public static function isValidDate(int $year, int $month, int $day): bool {
+        if($month < 1 || $month > 12)
+            return false;
+        if($day < 1 || $day > 31)
+            return false;
+
+        if($month === 2)
+            $days = $year === 0 || self::isLeapYear($year) ? 29 : 28;
+        elseif($month === 4 || $month === 6 || $month === 9 || $month === 11)
+            $days = 30;
+        else
+            $days = 31;
+
+        return $day <= $days;
+    }
+}
diff --git a/src/Users/User.php b/src/Users/User.php
index 5adfe03..4d85b6e 100644
--- a/src/Users/User.php
+++ b/src/Users/User.php
@@ -5,6 +5,7 @@ use DateTime;
 use DateTimeZone;
 use Index\XString;
 use Index\Colour\Colour;
+use Misuzu\DateCheck;
 use Misuzu\DB;
 use Misuzu\HasRankInterface;
 use Misuzu\Memoizer;
@@ -318,6 +319,10 @@ class User implements HasRankInterface {
         return new DateTime($this->user_birthdate ?? '0000-01-01', new DateTimeZone('UTC'));
     }
     public function setBirthdate(int $year, int $month, int $day): self {
+        // lowest leap year mariadb supports lol
+        // should probably split the date field and year field in the db but i'm afraid of internal dependencies rn
+        if($year < 1004)
+            $year = 1004;
         $this->user_birthdate = $month < 1 || $day < 1 ? null : sprintf('%04d-%02d-%02d', $year, $month, $day);
         return $this;
     }
@@ -652,14 +657,13 @@ class User implements HasRankInterface {
     }
 
     public static function validateBirthdate(int $year, int $month, int $day, int $yearRange = 100): string {
-        if($year > 0) {
-            if($year < date('Y') - $yearRange || $year > date('Y'))
+        if($day !== 0 && $month !== 0) {
+            if($year > 0 && ($year < date('Y') - $yearRange || $year > date('Y')))
                 return 'year';
-            $checkYear = $year;
-        } else $checkYear = date('Y');
 
-        if(!($day === 0 && $month === 0) && !checkdate($month, $day, $checkYear))
-            return 'date';
+            if(!DateCheck::isValidDate($year, $month, $day))
+                return 'date';
+        }
 
         return '';
     }