What is KakaoTalk?

KakaoTalk is the most popular messaging app in South Korea. It allows users to send messages, make calls, share files, and much more. For businesses, Kakao provides a suite of business communication APIs that enable direct interaction with their customers through the app.

The Main APIs Offered by Kakao

KakaoTalk Business provides brands with different messaging APIs to suit various communication needs. Here is an overview of the three most commonly used APIs:

💬 1. AlimTalk (Message Notification)

AlimTalk is designed for sending informative messages to users, even if they have not added the brand's channel as a friend.

It is primarly used for:

• Order, delivery, invoicing notifications
• Service or security alerts
• Account or event related information

🔒 AlimTalk messages must be sent using a pre-approved template by Kakao. Promotional content is prohibited.

👥 2. FriendTalk (Promotional Messages)

FriendTalk is designed for sending free messages that do not require prior validation. This is only possible, however, if the user has added the company's KakaoTalk channel as a friend.

It is used for:

• Promotions
• Special offers
• News and general marketing content

📅 Sending is restricted to authorized times (often 9am to 8pm local time).

🛠️ 3. CS Talk (Customer Support Chat)

CS Talk is designed to enable real-time conversations between a human agent (or chatbot) and a customer.
Ideal for:

• After-sales support
• Personalized inquiries
• Technical or commercial assistance

🤖 It is fully compatible with both chatbot integrations and use by human agents via a dedicated interface.

In a CS Talk conversation, your advisors and bots can send text, images, files and videos in MP4 format. From the conversation page, a video must not exceed 25 MB.

📄 Note: Sending videos is not available in FriendTalk and AlimTalk messages.

Outgoing Messages and the SenderKey.

To send messages via AlimTalk (notifications) and FriendTalk (promotional messages) on KakaoTalk, a SenderKey is required.

The SenderKey is a unique authentication key issued by Kakao that identifies and certifies the sending company.
It is tied to a validated production account and cannot be used with a test account.
This means you are unable to test sending outgoing AlimTalk or FriendTalk messages using a test KakaoTalk account.

It is designed to:

🛡️ Guarantee the security and reliability of messages,

✅ Limit abuse such as spam or unsolicited communications,

📬 Ensure traceability and compliance with the broadcasting rules specific to each channel.

Without a validated SenderKey, it is impossible to send AlimTalk or FriendTalk messages, even to test numbers. Note that this restriction does not apply to CS Talk, which is a conversational channel activated only with user consent.

Why Use KakaoTalk for Your Business?

📱 Maximum local reach: Over 90% of the South Korean population uses KakaoTalk.

🛡️ Secure and regulated communication

📈 Very high opening rates

🔌 Seamless API integration including CRM, automation, bots