Guide
Disclosure: ESIM KIMONO is our store. Competitor facts come from their own pages and public reviews, checked 13 October 2026, each linked.
Short answer: almost every "unlimited" Japan eSIM limits something: a daily allowance, a total allowance, or a speed cap. Our unlimited plans run on KDDI with no daily data ceiling and a flat 10 Mbps cap from the first minute to the last, enough for maps, video calls and HD streaming on a phone. If you need 4K or heavy laptop downloads, a fixed plan at full network speed suits you better.
You've filmed all day: the museum queue, the ramen counter, the city from the observation deck. Now you want to FaceTime home and post your favorite clip, and the video won't move. At the konbini till, the QR payment hangs. Your partner asks which exit, and the map is a grey grid.
Travelers write about exactly this moment:
Usually nothing is broken. The plan has a limit you only find when it kicks in.
| Provider | What actually limits you | Hotspot | Source |
|---|---|---|---|
| Nomad | Daily high-speed allowance (2GB a day per a review of the Japan plan), then 512 kbps until the 24h window resets | Not covered in our check | nomadesim.com, review |
| Ubigi | 25GB at full speed for the 7-day plan, then 2 Mbps | Not covered in our check | Ubigi plan page |
| Airalo | 3GB per 24h, then 1 Mbps for the rest of that 24h | Counts toward the 3GB | Airalo FUP |
| Holafly | Fair use may slow speed "for no more than one (1) day"; threshold not published | 1GB a day | holafly |
| Saily | 5GB per day, then up to 1 Mbps | Advertises "limitless hotspot sharing" | saily.com |
| Sakura Mobile (5G au) | Says "truly unlimited, with no speed restrictions" | 6GB per 7 days | Sakura support |
| ESIM KIMONO | Flat 10 Mbps cap. No daily or total allowance | Most plans; rule printed at checkout | /fup/ |
That's four kinds of limit:
Sakura Mobile is the one plan we checked that claims no speed limit. If hotspot isn't important to you, it's an honest option.
Because a rule you can read beats a limit you discover. Per our fair use page, 10 Mbps covers maps, transit, camera translation, chat, video calls, HD streaming on a phone and social media. It isn't enough for 4K or heavy laptop downloads; buy a fixed plan for those.
The honest trade-off: on a quiet 5G cell, a daily-allowance plan is faster than ours for the first few GB each day. Ours just never turns slow at dinner time.
Our sizing guide says most travelers use about 1GB a day. Find yourself here:
Why fixed can beat unlimited: a fixed plan runs at full network speed until the data is used, then slows to 384 kbps for the rest of the plan instead of cutting off. Messages still send and a map still loads. How much data do you need?
Unlimited doesn't help with no signal, the queue at Narita with your passport out. What we do:
ESIM KIMONO is run by Fizen LLC. Fizen.io has 500,000+ app users and a strategic investment from Tether. Card payments run on Stripe (PCI DSS Level 1). Our eSIMs are data only, and most can't be topped up: more data means a second eSIM.
Install on home Wi-Fi from the emailed QR code and leave the line off. On landing, turn it on, set it as the data line and enable Data Roaming. iPhone setup · Android setup · Narita · Haneda · Kansai
Sakura Mobile says its 5G plan has no speed restrictions, with hotspot capped. Every other plan we checked limits something: a daily allowance (Nomad, Airalo, Saily), a total allowance (Ubigi), an unpublished threshold (Holafly), or a flat speed cap (ESIM KIMONO, 10 Mbps).
Yes for maps, transit, translation, video calls, social media and HD streaming on a phone. No for 4K or heavy laptop downloads; a fixed plan suits those.
No. Our unlimited plans have no daily data ceiling. The 10 Mbps cap is the whole rule and applies from the first minute.
We don't compete on price. Plans are priced for a carrier-grade network and a human who answers. Today's price is on the button below.
Most of our plans allow it, with each rule printed at checkout. Hotspot shares the same 10 Mbps.
Competitor facts on this page were checked on 13 October 2026 on their own pages. The button above shows today's price.
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