diff --git a/src/chatgpt-api.ts b/src/chatgpt-api.ts
index 0d5cea8..2165956 100644
--- a/src/chatgpt-api.ts
+++ b/src/chatgpt-api.ts
@@ -37,7 +37,7 @@ export class ChatGPTAPI {
    * Creates a new client wrapper around OpenAI's chat completion API, mimicing the official ChatGPT webapp's functionality as closely as possible.
    *
    * @param apiKey - OpenAI API key (required).
-   * @param apiOrg - OpenAI API organization (optional).
+   * @param apiOrg - Optional OpenAI API organization (optional).
    * @param apiBaseUrl - Optional override for the OpenAI API base URL.
    * @param debug - Optional enables logging debugging info to stdout.
    * @param completionParams - Param overrides to send to the [OpenAI chat completion API](https://platform.openai.com/docs/api-reference/chat/create). Options like `temperature` and `presence_penalty` can be tweaked to change the personality of the assistant.
diff --git a/src/types.ts b/src/types.ts
index 16b64f2..2328584 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -10,7 +10,7 @@ export type ChatGPTAPIOptions = {
   /** @defaultValue `'https://api.openai.com'` **/
   apiBaseUrl?: string
 
-  apiOrg: string
+  apiOrg?: string
 
   /** @defaultValue `false` **/
   debug?: boolean