diff --git a/Flow.Launcher.Infrastructure/PinyinAlphabet.cs b/Flow.Launcher.Infrastructure/PinyinAlphabet.cs
index 7f55d8909..ca1e8be59 100644
--- a/Flow.Launcher.Infrastructure/PinyinAlphabet.cs
+++ b/Flow.Launcher.Infrastructure/PinyinAlphabet.cs
@@ -119,7 +119,7 @@ namespace Flow.Launcher.Infrastructure
         {
             var resultList = WordsHelper.GetPinyinList(content);
             var resultBuilder = new StringBuilder(_settings.UseDoublePinyin ? 3 : 4); // Pre-allocate with estimated capacity
-            var map = new TranslationMapping();
+            var map = new TranslationMapping(resultList.Length);
 
             var previousIsChinese = false;
 
@@ -157,10 +157,7 @@ namespace Flow.Launcher.Infrastructure
 
             map.EndConstruct();
 
-            var translation = resultBuilder.ToString();
-            var result = (translation, map);
-
-            return _pinyinCache[content] = result;
+            return _pinyinCache[content] = (resultBuilder.ToString(), map);
         }
 
         /// <summary>
diff --git a/Flow.Launcher.Infrastructure/TranslationMapping.cs b/Flow.Launcher.Infrastructure/TranslationMapping.cs
index e70443077..1d8cdc615 100644
--- a/Flow.Launcher.Infrastructure/TranslationMapping.cs
+++ b/Flow.Launcher.Infrastructure/TranslationMapping.cs
@@ -9,18 +9,38 @@ namespace Flow.Launcher.Infrastructure
 
         // Assuming one original item maps to multi translated items
         // list[i] is the last translated index + 1 of original index i
-        private readonly List<int> _originalToTranslated = new();
+        // Using short instead of int to save memory
+        private List<short> _originalToTranslatedBuilder;
+        private short[] _originalToTranslated;
+
+        public TranslationMapping(int capacityHint = 16)
+        {
+            _originalToTranslatedBuilder = new List<short>(capacityHint);
+        }
 
         public void AddNewIndex(int translatedIndex, int length)
         {
             if (_isConstructed)
                 throw new InvalidOperationException("Mapping shouldn't be changed after construction");
-            _originalToTranslated.Add(translatedIndex + length);
+
+            var value = translatedIndex + length;
+            if (value > short.MaxValue)
+                throw new ArgumentOutOfRangeException(nameof(translatedIndex),
+                    "Translation index exceeds maximum supported value (32,767)");
+
+            _originalToTranslatedBuilder.Add((short)value);
         }
 
         public int MapToOriginalIndex(int translatedIndex)
         {
-            var searchResult = _originalToTranslated.BinarySearch(translatedIndex);
+            if (_originalToTranslated == null)
+                throw new InvalidOperationException("Mapping must be constructed before use");
+
+            if (translatedIndex > short.MaxValue)
+                throw new ArgumentOutOfRangeException(nameof(translatedIndex),
+                    "Translation index exceeds maximum supported value (32,767)");
+
+            var searchResult = Array.BinarySearch(_originalToTranslated, (short)translatedIndex);
             return searchResult >= 0 ? searchResult + 1 : ~searchResult;
         }
 
@@ -28,6 +48,10 @@ namespace Flow.Launcher.Infrastructure
         {
             if (_isConstructed)
                 throw new InvalidOperationException("Mapping has already been constructed");
+
+            // Convert to array to save memory (no List overhead, no excess capacity)
+            _originalToTranslated = _originalToTranslatedBuilder.ToArray();
+            _originalToTranslatedBuilder = null; // Allow GC to collect the List
             _isConstructed = true;
         }
     }
diff --git a/Flow.Launcher.Test/TranslationMappingTest.cs b/Flow.Launcher.Test/TranslationMappingTest.cs
index a3c0026c0..0ec7021ff 100644
--- a/Flow.Launcher.Test/TranslationMappingTest.cs
+++ b/Flow.Launcher.Test/TranslationMappingTest.cs
@@ -57,15 +57,15 @@ namespace Flow.Launcher.Test
         private static int GetOriginalToTranslatedCount(TranslationMapping mapping)
         {
             var field = typeof(TranslationMapping).GetField("_originalToTranslated", BindingFlags.NonPublic | BindingFlags.Instance);
-            var list = (List<int>)field.GetValue(mapping);
-            return list.Count;
+            var array = (short[])field.GetValue(mapping);
+            return array.Length;
         }
 
         private static int GetOriginalToTranslatedAt(TranslationMapping mapping, int index)
         {
             var field = typeof(TranslationMapping).GetField("_originalToTranslated", BindingFlags.NonPublic | BindingFlags.Instance);
-            var list = (List<int>)field.GetValue(mapping);
-            return list[index];
+            var array = (short[])field.GetValue(mapping);
+            return array[index];
         }
     }
 }