diff --git a/index.d.ts b/index.d.ts
index e69de29..ab5043c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -0,0 +1,17 @@
+/**
+ * Convert an string into an object.
+ * 
+ * @param {string} input the string object
+ * @returns {object} the object similar to JSON.parse
+ * 
+ * @example
+ * ```
+ * import sTo = require('s-to-o');
+ * 
+ * sTo('a: a, b: b, c: 3, d: 7')
+ * // => { a: 'a', b: 'b', c: 3, d: 7 }
+ * ```
+ */
+declare function sTo(input: string): object
+
+export = sTo;
\ No newline at end of file
diff --git a/index.test-d.ts b/index.test-d.ts
index e69de29..b4b223c 100644
--- a/index.test-d.ts
+++ b/index.test-d.ts
@@ -0,0 +1,4 @@
+import { expectType } from 'tsd';
+import sTo = require('.');
+
+expectType<object>(sTo('a: a, b: b, c: 3, d: 7'));
\ No newline at end of file