diff --git a/package.json b/package.json
index 95addb5..5677b38 100644
--- a/package.json
+++ b/package.json
@@ -24,6 +24,7 @@
   ],
   "main": "index.js",
   "bin": "./bin/cli.js",
+  "types": "./types/index.d.ts",
   "scripts": {
     "istanbul": "babel-node ./node_modules/istanbul/lib/cli cover ./node_modules/mocha/bin/_mocha lib/**/*.spec.js",
     "test": "npm run istanbul -s",
diff --git a/types/index.d.ts b/types/index.d.ts
new file mode 100644
index 0000000..725b9b6
--- /dev/null
+++ b/types/index.d.ts
@@ -0,0 +1,31 @@
+
+declare module 'replace-in-file' {
+  function replaceInFile(config: ReplaceInFileConfig): Promise<ReplaceResults>;
+  function replaceInFile(config: ReplaceInFileConfig, cb: (error: Error, results: ReplaceResults) => void): void;
+  export default replaceInFile;
+
+  namespace replaceInFile {
+    export function sync(config: ReplaceInFileConfig): ReplaceResults;
+  }
+
+  export interface ReplaceInFileConfig {
+    files: string | string[];
+    from: string | RegExp | string[] | RegExp[] | FromCallback;
+    to: string | string[] | ToCallback;
+    countMatches?: boolean;
+    allowEmptyPaths?: boolean,
+    disableGlobs?: boolean,
+    encoding?: string,
+    dry?:boolean
+  }
+
+  export interface ReplaceResults {
+    file: string;
+    hasChanged: boolean;
+    numMatches?: number,
+    numReplacements?: number,
+  }
+}
+
+type FromCallback = (file: string) => string | RegExp | string[] | RegExp[];
+type ToCallback = (match: string, file: string) => string | string[];