KDDI Unlimited Data Japan eSIM｜Support ChatGPT
- Supports iOS one-click installation: Update to the latest iOS App version and iOS 17.4 or higher to install eSIM with one click in the KKday App.
- The only eSIM in the market directly operated by a telecom company in Japan, providing local network services by KDDI.
- Supports ChatGPT, unlimited data, unthrorottled 5G/4G high-speed mobile network.
- Enjoy an additional 3GB~15GB of hotspot data based on the number of days purchased.
- For physical Japan SIM cards, please refer to this product. [APP Exclusive Every Wednesday]
- Go to the "Download APP Gift Pack" or "Offers" section to claim a limited discount code and enjoy "50% off" ➤ Click here to download now
—KDDI won 1st place in Opensignal's 2025 Global Mobile Network Experience Awards for gaming, voice app, and network reliability experience categories—
Package Options
Product Info
The content of this product is provided by machine translation and may not reflect the actual information, please take this into consideration before booking.
No refunds after purchase; please confirm your phone's eSIM compatibility beforehand.
Before activating the eSIM, please update your iOS to the latest version and connect to a stable Wi-Fi network. Older iOS versions and unstable networks are common causes of eSIM activation failures.
Turn on the camera, scan the eSIM QR code, and tap "Add Cellular Plan."
Activation typically takes around 2–3 minutes. Any interruptions during this process may result in installation failure.
You can assign a label to each cellular plan, and customize your eSIM label by going to Settings and selecting Cellular.
Select the default line (Primary SIM) to designate the main phone number for receiving text messages. Please ensure that international roaming is activated for your main number with your original carrier to receive messages.
You can designate the primary SIM for iMessages and FaceTime.
Make sure to select eSIM as your cellular data plan. A common reason for being unable to access the internet is that eSIM mobile data is not enabled.
You can also manually add the eSIM if you're unable to scan the QR code.
After copying the eSIM activation code, please follow the steps to manually enter the eSIM information.
Purchase Notice
- The order cannot be canceled and refunded after sending the eSIM. Please confirm that the mobile phone can use eSIM first (iPhone and Android mobile phones sold in China, Hong Kong, and Macau do not support the eSIM function; most Android mobile phones sold in Taiwan do not support eSIM)
- For Android phones that can use eSIM, please refer to Figure 1 and Figure 2 for the steps to manually enter the activation code.
Reminders
Before purchasing, please enter "＊#0６#" on your mobile phone dial pad. If the EID serial number is displayed, you can use eSIM.
The QR Code can only be scanned once and does not support repeated installation. Please do not delete it after installation to ensure normal use of the service.
When enabling eSIM, please connect to a stable WiFi first to avoid activation failure due to network instability. After the eSIM expires, it cannot be reissued.
The validity period will only be calculated when you activate the eSIM after arriving in Japan. The first day will be from the moment it is activated to 24:00 pm Japan time.
It is normal to see "Activating" or "Activation Failed" when activating the eSIM outside of Japan. Upon arrival in Japan, please activate the eSIM to access the network.
This eSIM provides native network service directly from Japan KDDI (au) and is not a roaming service. Please keep Data Roaming turned off to ensure an optimal network experience.
How to Use
🔹 Before Installation – Please Confirm
- This eSIM provides native mobile network service from Japan KDDI (au) and is not an international roaming plan.
- Your phone must support eSIM functionality and be SIM-unlocked (not carrier-locked).
- Ensure you are connected to a stable Wi-Fi network during installation.
- It is recommended to install the eSIM either before departure or after arriving in Japan (to avoid activating it too early, which may affect usage days).
🔹 Step 1: Install the eSIM (Before Departure or Upon Arrival in Japan)
iPhone
- Go to Settings > Cellular
- Tap Add eSIM / Add Cellular Plan
- Scan the QR Code provided in your KKday voucher
- Follow the on-screen instructions to complete installation
- You may name the eSIM “KDDI Japan” for easy identification
Android
- Go to Settings > Network & Internet / SIM Card Management
- Tap Add eSIM / Add Cellular Plan
- Scan the QR Code provided in your KKday voucher
- Follow the on-screen instructions to complete installation
🔹 Step 2: Settings Upon Arrival in Japan (Important)
- Go to Settings > Cellular / SIM Management
- Enable this eSIM as your primary mobile data source
- Keep Data Roaming turned off (very important)
- Disable mobile data on any other SIMs not in use (to avoid accidental usage)
- Toggle Airplane Mode on and off once, then wait 1–2 minutes for connection
Cancellation Policy
- Once the order has been completed, it cannot be canceled, modified, or refunded
- Due to time zone differences, the confirmed cancellation date is based on the supplier’s local time. Please allow 2–5 business days to process your cancellation request, after which the cancellation fee will be charged according to the product’s cancellation policy. Once the cancellation is confirmed, you will receive your refund within 14 working days.
FAQ
The KDDI Japan eSIM utilizes the robust network of KDDI, a leading local Japanese telecom company. KDDI has been recognized by Opensignal's 2025 Global Mobile Network Experience Awards for excellence in gaming, voice app, and network reliability experience categories. This ensures reliable coverage and unthrottled 5G/4G high-speed mobile network performance across Japan, allowing for seamless connectivity.
Yes, the KDDI Japan eSIM provides unlimited data with unthrottled 5G/4G high-speed mobile network, ensuring you stay connected without speed reductions. Additionally, it offers an extra 3GB to 15GB of hotspot data, with the specific amount depending on the duration of your purchased plan, allowing you to share your connection.
The KDDI Japan eSIM is highly suitable for travelers visiting Japan. It offers instant connectivity, eliminating the need to swap physical SIM cards upon arrival. Being directly operated by a local telecom company (KDDI) in Japan, it provides reliable network services and consistent high-speed internet, ensuring a smooth and connected travel experience.
Installation of the KDDI Japan eSIM is designed for ease. If your device is updated to iOS 17.4 or higher and you have the latest app version, you can benefit from iOS one-click installation directly within the app. Otherwise, the process typically involves scanning a QR code provided after purchase or manually entering the eSIM details. Activation usually occurs automatically once you arrive in Japan and enable your eSIM.
Yes, the KDDI Japan eSIM fully supports mobile hotspot tethering. It includes an additional dedicated allocation of 3GB to 15GB of hotspot data, which varies based on the number of days purchased. This allows you to easily share your high-speed internet connection with other devices, such as laptops or tablets, for added convenience during your trip.
The iOS one-click installation feature simplifies the setup process for the KDDI Japan eSIM. If you have an iOS device updated to iOS 17.4 or higher and the latest version of the application, you can install your eSIM with just a single tap. This method streamlines activation, making it quicker and more user-friendly compared to traditional manual setup methods.
You can conveniently purchase your KDDI Japan eSIM through KKday. After completing your purchase, you will instantly receive your eSIM voucher, eliminating any waiting time. Booking via KKday ensures a seamless and efficient process, providing the benefit of immediate access to your connectivity needs for Japan without the hassle of physical SIM card handling.
The KDDI Japan eSIM offers several unique features for modern travelers. It specifically supports AI applications like ChatGPT, ensuring smooth and reliable access to these services. As the only eSIM in the market directly operated by a local Japanese telecom company, KDDI, it provides unparalleled local network service and unthrottled 5G/4G high-speed mobile internet.
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