Frequently asked questions

About the tool

Are my files uploaded to a server?

No. Reading the PDFs, building the file names, and creating the ZIP and index CSV all happen inside your browser. Loaded files are also cleared from the browser's memory when you close the page.

Which files are supported?

PDFs only. The free plan accepts up to 20 files per session and the paid plan has no limit (above 300 files, some computers may run out of browser memory).

Can it read scanned PDFs?

Automatic reading works only when the PDF contains text data. PDFs made by scanning paper or from photos have no text data and are marked "no text". You can still name them by entering the date, counterparty and amount by hand.

Is the automatically read information correct?

The date, amount and counterparty are estimated from the way invoices and receipts are usually written, so mistakes can happen. Automatically filled cells are shown in pale yellow. Select a row to see the first page of the PDF and compare.

Is this enough to meet the Electronic Books Preservation Act?

Dencho Rename helps with the search requirement (being able to find records by transaction date, amount and counterparty) by giving files systematic names and by creating an index book. You also need measures against tampering, such as setting and following internal rules. See File naming rules and How to make an index book for details, and confirm with a tax accountant or your tax office.

Where are my settings and counterparty dictionary stored?

In your browser's storage (localStorage). They are not sent to the server and do not carry over to other computers or browsers. Use "Export JSON" to save the counterparty dictionary and "Import JSON" in another browser. Clearing your browsing data also clears the settings and the dictionary.

Which browsers are supported?

It is built to work in the latest Chrome, Edge, Safari and Firefox. It also opens on smartphones, but a computer or tablet is recommended for checking and editing the table.

Pricing and payment

Who sells the paid plan?

Polar (Polar Software, Inc.) processes payments and sells the paid plan as the merchant of record. Polar handles payment, invoices and receipts, and tax collection. The operator of Dencho Rename sells through Polar.

Which payment methods can I use?

The methods shown on Polar's checkout page, such as credit cards.

Can I get a receipt or invoice?

You can download a receipt and an invoice for each order from Polar's customer portal. You can add a company name and address to the invoice. Sign in to the portal with the email address you used at checkout (customer portal).

Is a Japanese qualified invoice issued?

No. Polar Software, Inc. (USA), the seller of the paid plan, is not registered as a qualified invoice issuer in Japan (checked against the National Tax Agency's published data in September 2026). Polar's invoices do not show a registration number or a Japanese consumption tax amount.

Can I still claim the purchase tax credit without a qualified invoice?

According to the National Tax Agency, for this kind of service from a foreign business (consumer-oriented telecommunications services) bought from a business that is not a qualified invoice issuer, the transitional 80% credit cannot be used, but the small-amount exception can. The small-amount exception lets businesses with taxable sales of 100 million yen or less in the base period (among other conditions) claim the credit with only their books for purchases under 10,000 yen including tax made by September 30, 2029. The paid plan is ¥480 per month or ¥3,980 per year, so each payment is under 10,000 yen. Tax-exempt businesses and businesses using the simplified tax system pay the same amount of tax regardless of purchase invoices. See the National Tax Agency's pamphlet on cross-border services (Japanese) and ask a tax accountant if unsure.

How do I cancel?

You can cancel at any time from Polar's customer portal. After cancelling, the paid features stay available until the end of the paid period. There are no prorated refunds for cancelling mid-period.

Can I get a refund?

As a rule, paid fees are not refunded. However, if you bought twice by mistake, or a defect kept you from using the paid features and it could not be resolved, contact us and we will refund the full amount (Article 5 of the terms of service).

On how many computers can I use one license key?

In up to 3 browsers. To use it in a fourth, press "Remove" on the pricing page of a browser you no longer use, or delete an activation in Polar's customer portal.

I can't find my license key.

Contact

For bug reports, questions or refund requests, email support@dencho-rename.com. For refund requests, please include the email address you used at checkout.