Short answer
A fixed plan is one data allowance for that plan's duration, and a day pass is a daily allowance you buy for a number of days you choose. Whether you can top up, and what happens after the allowance, is on that plan's page.
Fact table
As of 2026-10-20
Each claim names its source. The full source list, with the date each page was read, is below.
| Claim | Source |
|---|---|
| On the Japan plan page, a day pass is the plan you buy by choosing a number of days, and its allowance is labeled for each day. Every other Japan plan is one allowance for that plan's own validity. | Wakamo Japan plan page |
| The day count on that page is a whole number from 1 to 365. | Wakamo Japan plan page |
| Each plan on that page shows its own data volume and its own validity. This page does not state either number. | Wakamo Japan plan page |
| When a fixed plan runs out of data, the plan page says the connection stops and that you are not charged for overage. | Wakamo Japan plan page |
| After a day pass's daily allowance, the plan page follows that plan's fair-use text. A text that states a speed says the connection slows to the speed stated for that plan. Any other text points you to the plan details. An empty text says the plan does not state what happens. Each version says you are not charged for overage. | Wakamo Japan plan page |
| The plan page says whether that plan can be topped up. When it can, you can add data for the same region within the validity period. When it cannot, the page says so and you buy another plan if you need more. A plan that could take extra days says those day extensions are not available to purchase yet. | Wakamo Japan plan page |
| Wakamo help says a day pass is sold by the day: you choose how many days. If the plan states a fair-use speed, the connection slows to the speed stated on the plan page, and you are not charged for overage. A top-up is offered only when the plan allows one. If the plan cannot be topped up, you buy another plan. Usage in your account can take time to update. | Wakamo help |
| When your account has a usage reading, remaining data is the total minus the volume used. That total is the updated total on the eSIM when one is stored, and otherwise the allowance of the plan you bought. The account calls the reading the last known usage and can mark it out of date. If the reading is missing, it says usage is unavailable. The figure is not split by day. | Wakamo account |
| Covered countries are the list on that plan. A day pass and a fixed plan each have their own list. Plan type does not add a country. | Wakamo Japan plan page |
FAQ
What is a fixed-data Japan plan?
It is a plan that is not sold as a day pass. It has one data volume and one validity length, both shown for that plan, and you buy it as one package. This page does not state either number.
What is a day pass?
It is a plan you buy by choosing the number of days, from 1 to 365, and the allowance is for each day.
Is a day pass unlimited?
This page states no speed. The plan page follows that plan's fair-use text, and you are not charged for overage.
Can I top up if I run out of data?
Only when that plan's page says you can add data for the same region within the validity period. If the page says the plan cannot be topped up, buy another plan.
Can I add days rather than data?
No. The plan page says a day-count extension is not available to purchase yet.
What happens when the data runs out?
On a fixed plan the connection stops. On a day pass, the plan page follows that plan's fair-use text. You are not charged for overage on either.
How do I check how much data is left?
In your account. When a usage reading exists, remaining data is the total minus the volume used. That total is the updated total on the eSIM when one is stored, and otherwise the allowance of the plan you bought. The account calls it the last known usage and can mark it out of date. If the reading is missing, it says usage is unavailable. It is not a separate total for the current day.
Can one plan cover Japan and another country?
Only if that plan's country list includes them. A day pass and a fixed plan each have their own list. Plan type does not add a country.
Which plan should I buy for a week or two?
This page does not pick a plan. On a day pass you set the day count, from 1 to 365. On a fixed plan the length is that plan's own validity.
Sources
Wakamo Japan plan pagewakamo.io
Wakamo product information. A day pass is bought by choosing a number of days, and its allowance is labeled for each day. Every other plan is one allowance for that plan's own validity. The page shows that plan's volume, validity, countries, top-up status, and what happens after the allowance. The day count stays inside 1 to 365. Day-count extensions are not available to purchase yet.
Accessed 2026-10-20.
Wakamo helpwakamo.io
Wakamo product information. A day pass is sold by the day: you choose how many days. If the plan states a fair-use speed, the connection slows to the speed stated on the plan page, and you are not charged for overage. A top-up is offered only when the plan allows one. If the plan cannot be topped up, you buy another plan. Usage in your account can take time to update.
Accessed 2026-10-20.
Wakamo accountwakamo.io
Wakamo product information. When a usage reading exists, remaining data is the total minus the volume used. That total is the updated total on the eSIM when one is stored, and otherwise the allowance of the plan you bought. The reading is the last known usage and can be marked out of date. If the reading is missing, usage is unavailable. The figure is not split by day.
Accessed 2026-10-20.