Do I need to create an account or install an app?

No installation or registration required. WariSaku is a web-based expense splitting app — just open the group URL in your browser and you're ready to go. Works on both iOS and Android smartphones as well as computers.

Is it free to use?

Completely free. No registration fees, monthly charges, or transaction fees.

How do I share the group URL with members?

After creating a group, you'll be taken to a share page where you can send the link via LINE, messaging apps, or have members scan a QR code. Anyone with the URL can access the group and record transactions.

How many people can use it?

From 2 to 20 members. WariSaku handles two-person splits as well as larger groups for trips, parties, shared housing, and more.

How do I actually send money after settling?

WariSaku calculates how much each person owes — the actual payment is handled directly between members using your preferred method (bank transfer, cash, etc.). The "Share via LINE" button lets you send the settlement summary to the group for easy payment requests.

Where is data stored and for how long?

Group data is securely stored in the cloud. Data is kept as long as the group exists, but groups that haven't been accessed for 180 days may be deleted without notice for service stability. Only members with the group URL can access the data.

Can I use it for overseas travel?

Yes! WariSaku supports 16 currencies including USD, EUR, KRW, TWD, THB, and more. You can enter amounts in the local currency and settle accordingly.

What happens with rounding?

You can set the rounding unit (1, 10, 100, or 1000) in group settings. The default is rounding up to the nearest 1 unit. Due to rounding, the total settlement amount may differ from the total amount paid by a few units — this is expected behavior, not an error.

What is weighted splitting?

You can assign each member a "ratio" to adjust their share of expenses. For example, setting a senior member to 2× and a junior to 1× will automatically split costs proportionally. This is handy for outings where some members pay more. Ratios can be changed in group settings.

Why are there so few settlement payments?

WariSaku uses a minimum-settlement algorithm. For a 5-person group that would normally require 10 payments, it automatically optimizes to just 3–4 payments. The algorithm finds the combination that minimizes the total number of transfers needed.

What makes WariSaku different from other apps?

The biggest advantage is that no account or installation is needed — just share a URL and multiple people can edit simultaneously. WariSaku also features automatic minimum-settlement calculation, weighted splitting with ratio settings, 16 currencies, and the ability to restore deleted transactions.

Can I use it on both smartphones and computers?

Yes. Open the same group URL on any device — smartphone, tablet, or computer — and you'll always see the latest data in real time. Different members can use different devices without any issues.

I lost my group URL. What can I do?

Groups you've visited are automatically saved in the "My Groups" list in your browser. Open WariSaku from the same device and browser to find your past groups. For access from a different device, you'll need the URL, so we recommend sharing it via LINE or a QR code in advance.

I entered a transaction incorrectly. Can I fix it?

Yes. Tap the pencil icon on any transaction to open the edit screen, where you can fix the amount, payer, date, or memo. You can also delete a transaction from the edit screen, and deleted transactions can be restored from the History page.

I want to delete the group.

Go to the group's Settings page and scroll to the bottom to find "Delete Group." Note that deleted groups cannot be restored. Individual transactions deleted via the History page can be restored.

Can I manage multiple groups at once?

Yes. The "My Groups" page lets you manage all your groups in one place — travel groups, dinner groups, shared housing, and more.

Can I use it without internet?

Previously viewed group data may be available via browser cache for viewing only, but recording transactions, settling, and syncing data all require an internet connection.

What is JPYC?

JPYC is a digital currency issued by JPYC Inc. that is pegged 1:1 to the Japanese yen (classified as an electronic payment instrument under Japan's Payment Services Act). WariSaku lets you display and copy wallet addresses on the settlement and settings screens. The actual transfer must be done by you using a JPYC-compatible wallet app — WariSaku does not send money automatically. You can also use JPYC to tip the developer. Note: WariSaku is not responsible for any issues related to JPYC transfers.

Is my personal information safe?

WariSaku requires no account registration, so we never collect personal information such as your name, email address, or phone number. Only members with the group URL can access the data, and we do not share any information with third parties. All communication is encrypted via HTTPS (SSL/TLS).