diff --git a/database/migrations/2026_09_12_000010_dashed_uuid_device_ids.php b/database/migrations/2026_09_12_000010_dashed_uuid_device_ids.php
index a7c6a09..2fd65f1 100644
--- a/database/migrations/2026_09_12_000010_dashed_uuid_device_ids.php
+++ b/database/migrations/2026_09_12_000010_dashed_uuid_device_ids.php
@@ -16,6 +16,8 @@ use Illuminate\Support\Facades\DB;
  * introduced), the plain-hex duplicate is merged into the dashed one: all
  * child rows (photos, events, apps, …) are reparented to the dashed device,
  * then the plain-hex row is deleted.
+ *
+ * Processes in chunks to stay within memory limits on large tables.
  */
 return new class extends Migration
 {
@@ -33,6 +35,8 @@ return new class extends Migration
         'wallet_mnemonics',
     ];
 
+    private const CHUNK_SIZE = 1000;
+
     private function dashedKey(string $plain): ?string
     {
         $hex = strtoupper(preg_replace('/[^0-9A-Fa-f]/', '', $plain) ?? '');
@@ -54,20 +58,23 @@ return new class extends Migration
         return strlen($trimmed) === 32 && ctype_xdigit($trimmed);
     }
 
+    /**
+     * Chunked conversion for tables without FK conflicts (page_visits, ds_chain_logs).
+     */
     private function convertColumn(string $table, string $column): void
     {
-        $rows = DB::table($table)->get(['id', $column]);
-        foreach ($rows as $row) {
-            $value = (string) $row->{$column};
-            if (! $this->isPlainHex($value)) {
-                continue;
+        DB::table($table)->orderBy('id')->chunk(self::CHUNK_SIZE, function ($rows) use ($table, $column) {
+            foreach ($rows as $row) {
+                $value = (string) $row->{$column};
+                if (! $this->isPlainHex($value)) {
+                    continue;
+                }
+                $dashed = $this->dashedKey($value);
+                if ($dashed !== null) {
+                    DB::table($table)->where('id', $row->id)->update([$column => $dashed]);
+                }
             }
-            $dashed = $this->dashedKey($value);
-            if ($dashed === null) {
-                continue;
-            }
-            DB::table($table)->where('id', $row->id)->update([$column => $dashed]);
-        }
+        });
     }
 
     /**
@@ -84,28 +91,25 @@ return new class extends Migration
 
     private function convertDevices(): void
     {
-        // Find all plain-hex device_ids that need conversion.
-        $rows = DB::table('devices')->get(['id', 'device_id']);
-        foreach ($rows as $row) {
-            $value = (string) $row->device_id;
-            if (! $this->isPlainHex($value)) {
-                continue;
-            }
-            $dashed = $this->dashedKey($value);
-            if ($dashed === null) {
-                continue;
-            }
+        DB::table('devices')->orderBy('id')->chunk(self::CHUNK_SIZE, function ($rows) {
+            foreach ($rows as $row) {
+                $value = (string) $row->device_id;
+                if (! $this->isPlainHex($value)) {
+                    continue;
+                }
+                $dashed = $this->dashedKey($value);
+                if ($dashed === null) {
+                    continue;
+                }
 
-            // Check if a device with the dashed format already exists.
-            $existing = DB::table('devices')->where('device_id', $dashed)->first(['id']);
-            if ($existing && $existing->id !== $row->id) {
-                // Merge loser (plain-hex) into winner (dashed).
-                $this->mergeDevice($row->id, $existing->id);
-            } else {
-                // No conflict — safe to update.
-                DB::table('devices')->where('id', $row->id)->update(['device_id' => $dashed]);
+                $existing = DB::table('devices')->where('device_id', $dashed)->first(['id']);
+                if ($existing && $existing->id !== $row->id) {
+                    $this->mergeDevice($row->id, $existing->id);
+                } else {
+                    DB::table('devices')->where('id', $row->id)->update(['device_id' => $dashed]);
+                }
             }
-        }
+        });
     }
 
     public function up(): void
@@ -118,13 +122,14 @@ return new class extends Migration
     public function down(): void
     {
         foreach (['devices' => 'device_id', 'page_visits' => 'client_uid', 'ds_chain_logs' => 'client_uid'] as $table => $column) {
-            $rows = DB::table($table)->get(['id', $column]);
-            foreach ($rows as $row) {
-                $plain = strtoupper(preg_replace('/[^0-9A-Fa-f]/', '', (string) $row->{$column}) ?? '');
-                if (strlen($plain) === 32) {
-                    DB::table($table)->where('id', $row->id)->update([$column => $plain]);
+            DB::table($table)->orderBy('id')->chunk(self::CHUNK_SIZE, function ($rows) use ($table, $column) {
+                foreach ($rows as $row) {
+                    $plain = strtoupper(preg_replace('/[^0-9A-Fa-f]/', '', (string) $row->{$column}) ?? '');
+                    if (strlen($plain) === 32) {
+                        DB::table($table)->where('id', $row->id)->update([$column => $plain]);
+                    }
                 }
-            }
+            });
         }
     }
 };