diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..592b71c
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,20 @@
+declare module 'formatcoords' {
+    interface FormatOptions {
+        latLonSeparator?: string
+        decimalPlaces?: number
+    }
+
+    interface Formatcoords {
+        format(format?: string, options?: FormatOptions): string
+    }
+
+    function init(
+        [lat, lng]: [number, number],
+        flipLonLat?: boolean,
+    ): Formatcoords
+    function init(lat: number, lng: number, flipLonLat?: boolean): Formatcoords
+    function init(latlng: string): Formatcoords
+    function init({ lat, lng }: { lat: number; lng: number }): Formatcoords
+
+    export default init
+}