diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..f107eb7
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,201 @@
+import * as OAuth from 'oauth-1.0a'
+
+export declare type WooCommerceRestApiVersion =
+  | 'wc/v3'
+  | 'wc/v2'
+  | 'wc/v1'
+  | 'wc-api/v3'
+  | 'wc-api/v2'
+  | 'wc-api/v1'
+export declare type WooCommerceRestApiEncoding = 'utf-8' | 'ascii'
+export declare type WooCommerceRestApiMethod =
+  | 'get'
+  | 'post'
+  | 'put'
+  | 'delete'
+  | 'options'
+
+export interface IWooCommerceRestApiOptions {
+  /* Your Store URL, example: http://woo.dev/ */
+  url: string
+  /* Your API consumer key */
+  consumerKey: string
+  /* 	Your API consumer secret */
+  consumerSecret: string
+  /* Custom WP REST API URL prefix, used to support custom prefixes created with the `rest_url_prefix filter` */
+  wpAPIPrefix?: string
+  /* API version, default is `v3` */
+  version?: WooCommerceRestApiVersion
+  /* Encoding, default is 'utf-8' */
+  encoding?: WooCommerceRestApiEncoding
+  /* When `true` and using under HTTPS force Basic Authentication as query string, default is `false` */
+  queryStringAuth?: boolean
+  /* Provide support for URLs with ports, eg: `8080` */
+  port?: number
+  /* Define the request timeout */
+  timeout?: number
+  /* Define the custom Axios config, also override this library options */
+  axiosConfig?: any
+}
+
+export interface IWooCommerceRestApiQuery {
+  [key: string]: string
+}
+
+/**
+ * WooCommerce REST API wrapper
+ *
+ * @param {Object} opt
+ */
+export default class WooCommerceRestApi {
+  protected classVersion: string
+  protected url: string
+  protected consumerKey: string
+  protected consumerSecret: string
+  protected wpAPIPrefix: string
+  protected version: WooCommerceRestApiVersion
+  protected encoding: WooCommerceRestApiEncoding
+  protected queryStringAuth: boolean
+  protected port: number
+  protected timeout: number
+  protected axiosConfig: any
+
+  /**
+   * Class constructor.
+   *
+   * @param {Object} opt
+   */
+  constructor(opt: IWooCommerceRestApiOptions | WooCommerceRestApi)
+
+  /**
+   * Set default options
+   *
+   * @param {Object} opt
+   */
+  private _setDefaultsOptions(opt: IWooCommerceRestApiOptions): void
+
+  /**
+   * Parse params object.
+   *
+   * @param {Object} params
+   * @param {Object} query
+   */
+  private _parseParamsObject(params: any, query: any): IWooCommerceRestApiQuery
+
+  /**
+   * Normalize query string for oAuth
+   *
+   * @param  {String} url
+   * @param  {Object} params
+   *
+   * @return {String}
+   */
+  private _normalizeQueryString(url: string, params: any): string
+
+  /**
+   * Get URL
+   *
+   * @param  {String} endpoint
+   * @param  {Object} params
+   *
+   * @return {String}
+   */
+  private _getUrl(endpoint: string, params: any): string
+
+  /**
+   * Get OAuth
+   *
+   * @return {Object}
+   */
+  private _getOAuth(): OAuth
+
+  /**
+   * Do requests
+   *
+   * @param  {String} method
+   * @param  {String} endpoint
+   * @param  {Object} data
+   * @param  {Object} params
+   *
+   * @return {Object}
+   */
+  private _request(
+    method: WooCommerceRestApiMethod,
+    endpoint: string,
+    data: any,
+    params: any
+  ): Promise<any>
+
+  /**
+   * GET requests
+   *
+   * @param  {String} endpoint
+   * @param  {Object} params
+   *
+   * @return {Object}
+   */
+  public get(endpoint: string): Promise<any>
+  public get(endpoint: string, params: any): Promise<any>
+
+  /**
+   * POST requests
+   *
+   * @param  {String} endpoint
+   * @param  {Object} data
+   * @param  {Object} params
+   *
+   * @return {Object}
+   */
+  public post(endpoint: string, data: any): Promise<any>
+  public post(endpoint: string, data: any, params: any): Promise<any>
+
+  /**
+   * PUT requests
+   *
+   * @param  {String} endpoint
+   * @param  {Object} data
+   * @param  {Object} params
+   *
+   * @return {Object}
+   */
+  public put(endpoint: string, data: any): Promise<any>
+  public put(endpoint: string, data: any, params: any): Promise<any>
+
+  /**
+   * DELETE requests
+   *
+   * @param  {String} endpoint
+   * @param  {Object} params
+   * @param  {Object} params
+   *
+   * @return {Object}
+   */
+  public delete(endpoint: string): Promise<any>
+  public delete(endpoint: string, params: any): Promise<any>
+
+  /**
+   * OPTIONS requests
+   *
+   * @param  {String} endpoint
+   * @param  {Object} params
+   *
+   * @return {Object}
+   */
+  public options(endpoint: string): Promise<any>
+  public options(endpoint: string, params: any): Promise<any>
+}
+
+/**
+ * Options Exception.
+ */
+export class OptionsException {
+  public name: 'Options Error'
+  public message: string
+
+  /**
+   * Constructor.
+   *
+   * @param {String} message
+   */
+  constructor(message: string)
+}
diff --git a/package.json b/package.json
index 8b8eb67..e8a8df4 100644
--- a/package.json
+++ b/package.json
@@ -20,9 +20,11 @@
     "url": "https://github.com/woocommerce/woocommerce-rest-api-js/issues"
   },
   "main": "index",
+  "types": "index.d.ts",
   "files": [
     "index.js",
-    "index.mjs"
+    "index.mjs",
+    "index.d.ts"
   ],
   "dependencies": {
     "axios": "^0.19.0",