diff --git a/code/AssetLib/glTF/glTFImporter.cpp b/code/AssetLib/glTF/glTFImporter.cpp
index db587ad69..744b1d1e3 100644
--- a/code/AssetLib/glTF/glTFImporter.cpp
+++ b/code/AssetLib/glTF/glTFImporter.cpp
@@ -93,7 +93,7 @@ const aiImporterDesc *glTFImporter::GetInfo() const {
 bool glTFImporter::CanRead(const std::string &pFile, IOSystem *pIOHandler, bool /* checkSig */) const {
     glTF::Asset asset(pIOHandler);
     try {
-        asset.Load(pFile, CheckMagicToken(pIOHandler, pFile, AI_GLB_MAGIC_NUMBER, AI_COUNT_OF(AI_GLB_MAGIC_NUMBER)));
+        asset.Load(pFile, CheckMagicToken(pIOHandler, pFile, AI_GLB_MAGIC_NUMBER, strlen(AI_GLB_MAGIC_NUMBER)));
         return asset.asset;
     } catch (...) {
         return false;
@@ -697,7 +697,7 @@ void glTFImporter::InternReadFile(const std::string &pFile, aiScene *pScene, IOS
 
     // read the asset file
     glTF::Asset asset(pIOHandler);
-    asset.Load(pFile, CheckMagicToken(pIOHandler, pFile, AI_GLB_MAGIC_NUMBER, AI_COUNT_OF(AI_GLB_MAGIC_NUMBER)));
+    asset.Load(pFile, CheckMagicToken(pIOHandler, pFile, AI_GLB_MAGIC_NUMBER, strlen(AI_GLB_MAGIC_NUMBER)));
 
     //
     // Copy the data out
diff --git a/code/AssetLib/glTF2/glTF2Importer.cpp b/code/AssetLib/glTF2/glTF2Importer.cpp
index 6371d2bd5..824fa7fcd 100644
--- a/code/AssetLib/glTF2/glTF2Importer.cpp
+++ b/code/AssetLib/glTF2/glTF2Importer.cpp
@@ -113,7 +113,7 @@ bool glTF2Importer::CanRead(const std::string &filename, IOSystem *pIOHandler, b
     if (pIOHandler) {
         glTF2::Asset asset(pIOHandler);
         return asset.CanRead(filename, CheckMagicToken(pIOHandler, filename, AI_GLB_MAGIC_NUMBER,
-                                                       AI_COUNT_OF(AI_GLB_MAGIC_NUMBER)));
+                                                       strlen(AI_GLB_MAGIC_NUMBER)));
     }
 
     return false;
@@ -1679,7 +1679,7 @@ void glTF2Importer::InternReadFile(const std::string &pFile, aiScene *pScene, IO
 
     // read the asset file
     glTF2::Asset asset(pIOHandler, static_cast<rapidjson::IRemoteSchemaDocumentProvider *>(mSchemaDocumentProvider));
-    asset.Load(pFile, CheckMagicToken(pIOHandler, pFile, AI_GLB_MAGIC_NUMBER, AI_COUNT_OF(AI_GLB_MAGIC_NUMBER)));
+    asset.Load(pFile, CheckMagicToken(pIOHandler, pFile, AI_GLB_MAGIC_NUMBER, strlen(AI_GLB_MAGIC_NUMBER)));
     if (asset.scene) {
         pScene->mName = asset.scene->name;
     }