Internet in Japan: What Every Traveller Needs to Know
Japan is one of the most connected countries in the world. Mobile coverage is excellent, 5G is widespread in major cities, and the infrastructure for travellers has improved dramatically over the past several years. But Japan also has a few quirks when it comes to getting online, and knowing what to expect before you arrive will save you time and money.
This guide covers everything from how to get data in Japan to which apps you actually need, how connectivity works on the famous Shinkansen, and why an eSIM beats the alternatives for most travellers.
How to Get Internet Access in Japan
There are three main ways travellers get online in Japan: pocket Wi-Fi rentals, local SIM cards, and travel eSIMs. Here is how they compare.
Pocket Wi-Fi
Pocket Wi-Fi devices were the go-to solution for travellers in Japan for years. You rent a portable hotspot unit, pick it up at the airport, and connect your phone to it via Wi-Fi wherever you go. The problems are that you have to carry an extra device, keep it charged, and return it before you leave. If you are travelling as a group and want to share data between multiple people, it still makes sense. For solo travellers or couples, a travel eSIM is simpler.
Local SIM cards
You can buy a Japanese SIM card at major airports and electronics stores. These are data-only SIMs sold by carriers like IIJmio and NTT Docomo. They work well, but you have to swap out your existing SIM when you insert them, which means losing access to your home phone number while it is out. You also need to find a shop and go through the setup process after you land.
Travel eSIM
A travel eSIM like Pocket Roam is the cleanest option for most travellers. You buy and install it at home before your trip, it sits on your phone alongside your regular SIM, and you are online the moment you land without stopping anywhere or swapping anything. Your home number stays active for calls while the eSIM handles all your data.
What Mobile Coverage is Like in Japan
Japan's mobile network is one of the strongest in Asia. In Tokyo, Osaka, Kyoto, Hiroshima, and most other major cities, you can expect fast 4G or 5G across almost the entire urban area, including on the subway.
Outside the cities, coverage is still solid along main roads and in regional towns. Rural areas and mountain regions can have weaker signal, but for the typical Japan itinerary that covers popular destinations, you will have reliable data throughout.
One thing worth noting: Japan's underground stations and tunnels often have surprisingly good coverage. Many subway lines in Tokyo have mobile signal on the platforms and even in the carriages, which is not always the case in other countries.
Does Your eSIM Work on the Shinkansen?
Yes, with some caveats. The Shinkansen (bullet train) travels at speeds of up to 320km/h, and signal can drop briefly as you pass through tunnels. In open stretches between cities you will generally have a usable connection, though speeds fluctuate.
For browsing, messaging, and maps, it works fine. For video streaming or calls, expect some interruptions depending on the route. The Tokyo to Osaka route on the Tokaido Shinkansen has decent coverage for most of the journey. Routes through the Japanese Alps and more remote areas of Tohoku can be patchier.
If you want to work on the train, downloading what you need before boarding is a smart move.
Essential Apps for Travelling in Japan
Having the right apps downloaded and set up before you arrive will make your trip significantly smoother. Here are the ones worth having:
Navigation and transport
Google Maps works well in Japan and handles train routing accurately, including transfers between different rail lines. For something more detailed for train travel specifically, the Hyperdia or Navitime Japan Travel apps are worth looking at.
Suica is the digital transit card used across most of Tokyo's train and subway network, and it is now available as a digital card on iPhone and many Android phones. Load it up before you arrive and tapping in and out of stations becomes effortless.
Offline maps
Download Japan (or specific regions like Tokyo or Kyoto) in Google Maps before you leave home. This gives you navigation that works even with no signal, and saves your data allowance for other things.
Translation
Google Translate's camera feature is genuinely useful in Japan for reading menus, signs, and station displays. Download the Japanese language pack in the app before you travel so it works offline.
Payments
Japan is still largely a cash society, but IC cards like Suica work for transit and convenience stores. Some restaurants and shops now accept Apple Pay and Google Pay, especially in cities. Having a Wise or Revolut card loaded up is handy for ATM withdrawals at 7-Eleven or Japan Post ATMs, which reliably accept international cards.
Food and recommendations
Google Maps restaurant reviews work well in Japan. Tabelog is a popular Japanese restaurant review site with an English option, and it tends to surface more local spots than tourist-focused platforms.
Can You Use Wi-Fi in Japan?
Yes, Wi-Fi is available in most hotels, cafes, and convenience stores. 7-Eleven, Lawson, and FamilyMart all offer free Wi-Fi. Major stations and some train lines also have public Wi-Fi.
That said, public Wi-Fi in Japan often requires you to register or go through a login page each time you connect, which can be fiddly. You also cannot always rely on it for speed or security. Your Pocket Roam eSIM gives you a consistent, private connection that you control, so you are not dependent on finding a working hotspot every time you need data.
How Much Data Do You Need in Japan?
For a standard week in Japan using maps, messaging, and occasional social media, most travellers get by comfortably on 5GB. If you are uploading a lot of content, streaming music on trains, or making regular video calls, 10GB to 20GB gives you more headroom.
Here is a quick breakdown of what common activities use:
- Google Maps navigation: roughly 5MB per hour
- Messaging on WhatsApp: very little, under 1MB for a typical conversation
- Streaming music on Spotify: around 40MB to 150MB per hour depending on quality
- Uploading photos to Instagram: roughly 3MB to 5MB per image
- Video calls on WhatsApp or FaceTime: around 250MB to 400MB per hour
If you are using Japan Rail Pass and spending long hours on trains, download podcasts and playlists before you board rather than streaming, and your data will last considerably longer.
A Note on Calling and SMS in Japan
Pocket Roam eSIMs are data-only plans, which is the case for most travel eSIMs. You will not get a Japanese phone number and you cannot send traditional SMS messages through the eSIM. For calls and messages, use data-based apps like WhatsApp, FaceTime, Skype, or Line, which are all free to use over a data connection.
Your home SIM stays active in the background, so if you receive a call on your regular number while in Japan, it will still come through. Just make sure data roaming is turned off on your home SIM so you are not charged roaming fees on data in the background.
Get Connected Before You Land
The easiest way to make sure you are online the moment you arrive in Japan is to sort your eSIM before you leave home. Install it, confirm it is on your device, and when you land at Narita, Haneda, or Kansai, you will be connected before you reach baggage claim.
Browse Pocket Roam Japan eSIM plans starting from $6 USD, with both fixed data and unlimited options available.
