Is an eSIM worth it for your trip?
Yes, by a wide margin. Your carrier's day pass charges $12 for every day you use data abroad, while one eSIM plan covers the whole trip.
Your carrier's day pass AT&T or Verizon, $12 a day
Total $120.00$120.00
Ubigi eSIM 10 GB, 30 days
Total $16.50$16.50
You keep $103.50
A day pass starts the first time your phone uses data abroad.
How much data do I need for 2 weeks in Japan?
About 10 GB, if you use maps, LINE and Instagram on a normal day. That is about 0.7 GB a day. Post a lot or call home on video most evenings and 20 GB is the safer size.
Hotels and many train stations in Japan have free Wi-Fi, so long calls and streaming in your room cost you nothing. Your eSIM mostly carries you through the street and the train, which is why a fixed plan is enough for most trips.
| Trip | Maps and messages | Plus some social | Plus social all day | Plus an hour of video |
|---|---|---|---|---|
| 1 week | 5 GBabout 1.5 GB | 5 GBabout 5 GB | 10 GBabout 8.5 GB | Unlimitedabout 26 GB |
| 10 days | 5 GBabout 2 GB | 10 GBabout 7 GB | 20 GBabout 12 GB | 50 GBabout 37 GB |
| 2 weeks | 5 GBabout 3 GB | 10 GBabout 10 GB | 20 GBabout 17 GB | Unlimitedabout 52 GB |
| 3 weeks | 5 GBabout 4 GB | 20 GBabout 15 GB | 25 GBabout 25 GB | Unlimitedabout 78 GB |
An hour of HD streaming a day is added on top of some social media. From 20 to 50 GB, a big fixed plan (Ubigi 25 GB at $32.00, Nomad 50 GB at $35.00) costs less than unlimited on trips of 10 days or more.
10 GB for two weeks in Japan: Ubigi, about $16.50 for 30 days, on Docomo and KDDI.
Get Ubigi 10 GB for JapanHow many GB of data should I get for an eSIM?
Count what you do each day, multiply by your days, then buy the next size up. These are the figures the calculator uses. They are rough, because two people scrolling the same app can use very different amounts.
Maps, train times and messages
about 0.2 GB a daySocial media and photos, some or all day
about 0.5 to 1 GB a dayAn hour of browsing on a laptop hotspot
about 0.1 to 0.2 GBAn hour of video calls, phone or laptop
about 1 GBAn hour of HD streaming
about 3 GBThe plan sizes the calculator picks from are 5, 10 and 20 GB, then unlimited, the sizes almost every provider sells. In Japan it also offers 25 and 50 GB plans when they cost less than unlimited. Going from 5 GB to 10 GB there costs about $6.50 more.
Is 10 GB enough for a week?
Yes, for almost everyone. 10 GB over 7 days is about 1.4 GB a day, enough for maps, social media all day and a ten-minute video call home.
Where 10 GB runs out is streaming. One hour of HD video a day takes about 3 GB, so a week of it on the train needs about 21 GB for the video alone. If that sounds like you, an unlimited plan is the simpler buy. In Japan, Holafly is $27.50 for 7 days.
Unlimited data or a fixed plan?
Take a fixed plan unless you stream every day. Most "unlimited" plans run at full speed for a set amount each day, then slow down until the next day. The international guide compares them side by side.
In Europe, a short trip flips the math. Airalo's unlimited Eurolink for 7 days costs $27.00, less than its 10 GB plan at $31.00, so the calculator picks unlimited when your week needs more than 5 GB.
Working from a laptop on your hotspot? Holafly's unlimited plan shares only 1 GB a day with a laptop. In Japan, take a big fixed plan that allows hotspot: Nomad 50 GB for 30 days at $35.00, on KDDI, or Ubigi 25 GB at $32.00, on Docomo and KDDI. A laptop uses roughly 100 to 200 MB an hour for browsing and email, and about 1 GB for an hour of video calls. Turn off automatic updates and cloud sync before you connect.
Travel data questions
How many GB of eSIM for 2 weeks?
10 GB for a normal two weeks of maps, messages and social media. 20 GB if you share a lot of photos and videos or make video calls most days. Unlimited if you stream video on the go.
How many GB of data should I get for eSIM?
Count about 0.2 GB a day for maps and messages, about 0.5 to 1 GB more for social media and photos, about 1 GB per hour of video calls and about 3 GB per hour of HD streaming. A laptop on your hotspot uses roughly 100 to 200 MB an hour for browsing. Multiply by your days and buy the next plan size up.
Is 20 GB enough for 2 weeks in Japan?
Yes, with room to spare for most travelers. 20 GB over 14 days is about 1.4 GB a day, enough for maps, social media all day and short video calls. Only daily streaming away from Wi-Fi, or a laptop on your hotspot every day, would need more.
Can I buy an eSIM just for data?
Yes. The travel eSIMs on this page sell data plans. Keep your US line on for your number, with its data roaming off, and iMessage and WhatsApp work over the eSIM's data. The iPhone setup guide shows each switch.
Does Holafly's unlimited data plan have a daily limit?
Holafly publishes no daily full-speed cap for Japan. Sharing it as a hotspot with a laptop is limited to 1 GB a day, so for laptop work a big fixed plan fits better: in Japan, Nomad 50 GB for 30 days at $35.00, with hotspot allowed.