eSIM for Japan

The cheapest ones that genuinely allow tethering, and all five do. Holafly is out: it's the priciest of the nine and caps tethering at 1 GB a day, and Saily gets in on price with one catch, an unlimited that drops to 1 Mbps past 5 GB in a day.

Checked on their own pages on October 2, 2026, and they go about it three different ways.

Airalo and Saily publish a real dollar catalog, and you can tell because the ratio between their dollar and euro prices shifts from one plan to the next instead of holding steady. Ubigi charges the same number in dollars as in euros: $16.50 where a European pays €16.50, which is about 14 percent less once you convert. That's a pricing choice, not a display bug. The same page in pounds returns £13.50. Yesim goes the other way and multiplies its euro price by exactly 1.20 across all 35 plans, when the reference rate sits at 1.1578. Yesim's dollar buyer pays about 3.6 percent extra. That alone is reason to weigh the other four first.

None of the five gives you one. Messaging apps cover reaching people. It only matters if you have to leave a local number someone can call, for a restaurant booking say, and that means going through a Japanese carrier, more expensive and booked before you fly.

None of these sellers owns a single antenna. They all rent from the three Japanese carriers, and that choice decides your coverage. Docomo (Ubigi) reaches farthest up the valleys and holds up on the islands. KDDI (Ubigi, Nomad, Airalo, Yesim, Saily) covers cities and their edges very well, and Yesim is the only one of the five renting nothing else. SoftBank (Nomad, Airalo, Saily) is fastest downtown and fades soonest deep in the countryside. In Tokyo or Kyoto all three work everywhere and the question doesn't arise.

The headline price on the Ubigi and Saily rows is a discount of our own, negotiated with them: 10 percent at Ubigi on a first order, 15 percent at Saily. It applies automatically when you click the button. No code to type. The list price stays underneath.

A row marked on sale is different: the seller has cut its price for everyone, not just for you. That's what you pay today, with the normal price next to it.

Rough daily figures, hotel and public wifi excluded.

These figures cross-check what the app publishers state against average French consumption measured by Arcep, 17 GB a month per subscriber. The 250 MB floor is our own estimate, and we have not found a public source that measures what a tourist actually uses in a day in Japan, so treat that number as a starting point rather than a measurement. What is solid: GPS costs almost nothing. Satellite positioning is free; only map tiles and live traffic use data, a handful of megabytes an hour. A full day walking around stays under 80 MB.

It runs from almost nothing to four times the price, which is why this page won't decide for you.

Two weeks can mean 3 GB or 19 GB, depending on whether you check maps or watch video on the subway. The price follows. On light use the fixed plan costs a quarter as much as unlimited. On heavy use over a single week the gap nearly closes.

Run the whole grid, every length up to a month and every usage the calculator covers, and unlimited never wins, because the cheapest 50 GB plan on the board absorbs even the heaviest need the calculator can produce.

One case escapes that arithmetic, and it's real: downloading films, gaming online, working on video calls all day. That's beyond the few gigabytes a normal trip uses. Unlimited becomes the right buy again, and if that's your trip you already know it, so the calculator above isn't built for you.

The cheapest headline rate, Ninja WiFi at about $3 (¥440) a day, buys 1 GB a day for the whole group, which split four ways is 250 MB each, the floor for one day of sightseeing and nothing more. The tier that actually covers a group starts at 3 GB a day, about $5 (¥770) a day.