Using Pennyweight in Japan

Pennyweight links banks in the US only, so Japanese accounts use statement import. You add each account by hand in yen (JPY), and your AI reads your bank's statement files into it. New to this? Start with use Pennyweight without a bank link.

What Japanese bank files look like

Formats differ from bank to bank. Two examples from the banks' own business banking documentation:

• MUFG BizSTATION. The all-transactions CSV is encoded in Shift-JIS. Dates are written as YYYY.MM.DD without leading zeros, such as 2026.1.2. Payments, deposits and the balance sit in separate yen columns.
• Kyoto Bank. Its business web banking also offers a statement file in the Japanese Bankers Association's standard layout. That file writes dates in the Japanese era calendar as YYMMDD, and marks each amount as a deposit or a withdrawal instead of giving it a sign.

Let your AI read the file

Pennyweight can also read a CSV file directly, but that route is a poor fit here. It reads a file that isn't UTF-8 as Windows-1252, so Japanese text such as 摘要 descriptions comes out garbled. It also converts dates in only five forms, and only once your AI names the form: YYYY-MM-DD, MM/DD/YYYY, DD/MM/YYYY, DD.MM.YYYY and YYYYMMDD. Dates such as 2026.1.2, 2026/01/02 or era dates aren't among them, and one date it can't convert blocks the whole file. For the details, see bank CSVs with decimal commas, semicolons and day-first dates.

Instead, your AI opens the file in your chat and sends the transactions to Pennyweight as rows. Each row needs a YYYY-MM-DD date and a signed amount: money in positive, money out negative. So your AI converts the dates, including era dates, and turns the withdrawal column into negative amounts.

How to do it

1. Ask your AI to add an account with JPY as its currency. Give the balance before your file's first transaction as its opening balance. A new manual account needs one before its first import saves.
2. Share the CSV with your AI, name the account, and mention the encoding if you know it.
3. Check the preview: the number of rows, that withdrawals are negative, and the account's balance after the import. That balance should equal the file's last balance. See balance looks wrong after an import.
4. Say yes. Your AI saves the rows and reports how many went in.

What you'll see

Your AI adds Yen Checking in JPY, reads the file and shows a preview with the count of new rows and the account's balance after the import. Yen amounts are shown in whole yen, with no decimals. For this file, the balance after the import matches the last value in its balance column. Once you confirm, your AI tells you how many rows it saved to Yen Checking.

If your AI can't read the Japanese text in the file, ask it to try the file as Shift-JIS, or save a UTF-8 copy and share that.

Good to know

• Whole yen. Pennyweight stores JPY in whole yen. An amount sent with decimals is rounded to the nearest yen. See fix foreign-currency amounts that look 100x too large.
• Yen stays yen. Rows without their own currency take the account's currency. Each amount is stored in its own currency and is never converted. Totals that combine your ledgers, such as your net worth, keep the figures per currency and add one figure in your display currency. See choose the currency for totals across ledgers and accounts and totals in more than one currency.
• Opening balance later. If you skipped it, see set or correct an opening balance.
• Checking each month. To compare an account with a statement's closing balance, see reconcile against a statement.