diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..fda0350
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,9 @@
+export as namespace geocluster;
+export = geocluster;
+
+interface Result {
+    centroid: number[];
+    elements: number[][];
+}
+
+declare function geocluster (elements: number[][], bias: number): Result[];