How to test Japanese demand for your product before you commit to Japan

The question overseas founders ask us is rarely "Is Japan a good market?". They already know it is. The real question is: will Japanese customers buy this product, at this price, explained this way?

A market report can't answer that. Japanese buyers can. And in Japan there is a well-worn route for asking them without building inventory first: a small paid test, followed by a pre-order campaign on a Japanese crowdfunding platform.

In Japan, the sign-up list is often built on LINE, the messaging app most people in the country use every day. Brands send launch news there the way they would use email elsewhere.

Before you spend on ads, set a ceiling for what one sign-up may cost. The formula we use is simple:

• Maximum cost per sign-up = profit per unit × the share of sign-ups you expect to buy
• Example: if you make ¥10,000 per unit and about 1 in 10 sign-ups buys, a sign-up can cost up to ¥1,000

If the test brings sign-ups in well under that ceiling, you have a launch worth scaling. If it can't get close, you have learned something important for the price of a small ad budget, not a container of stock.

Japanese crowdfunding works like a pre-order store with an audience. A campaign that starts strong climbs the platform's rankings, and the rankings bring in people who have never heard of the brand.

That is why the first day matters most. One example from a brand we support: an overseas travel stroller opened on Makuake on October 31, 2026. The first 20 units at the earliest price sold out in 9 minutes, and within five days it had 41 buyers, about ¥3.1M, and a place in the platform's top 5. Before launch, close to 30 people had told the team they would definitely buy, and more than ten said they had been waiting two years for it to reach Japan.

Then expect a slow middle. In the COFFEEJACK campaign on GREEN FUNDING, the first ¥5M came in 8 days and the next ¥5M took 53 days. Regular updates to backers are what carry a campaign through that stretch.

• It can tell you whether Japanese buyers want the product enough to pay before it ships.
• It can tell you which version and which price they choose. Often it is not the cheapest one.
• It can't tell you that a slow start means a bad product. Very often it means the message or the target customer is off, and that can be fixed.

One Korean coffee appliance we launched raised about ¥4M in its first campaign. After talking to the people who had actually bought it, we found the real customers were older than we had assumed. With a rebuilt page and new ads, it sold about ¥18M in the next three months through our own online store.

We buy a small first order at wholesale and pay for the Japanese side of the test ourselves: localization, the landing page, ads, the crowdfunding campaign and support. You see real Japanese demand before deciding how far to go together.