diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..cb16122
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,34 @@
+# EditorConfig — consistent style across editors for PredictionCastAI C++ repos
+# https://editorconfig.org/
+# Matches the fleet-standard .clang-format: tab-indent (width 4), LF, UTF-8.
+
+root = true
+
+[*]
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.{cpp,hpp,c,h,cc,cxx,hxx}]
+indent_style = tab
+indent_size = 4
+max_line_length = 100
+
+[*.{cmake,CMakeLists.txt}]
+indent_style = tab
+indent_size = 4
+
+[Makefile]
+indent_style = tab
+
+[*.{yml,yaml}]
+indent_style = space
+indent_size = 2
+
+[*.{json,jsonc}]
+indent_style = space
+indent_size = 2
+
+[*.md]
+trim_trailing_whitespace = false