BAI2 to CSV Converter

A BAI2 file is comma separated, so the obvious shortcut is to rename it .csv and open it directly. That fails, because BAI2 is a record format, not a table: every line starts with a two digit record code that changes the meaning of every field after it. A spreadsheet has no idea that 16 means "transaction detail" and 03 means "new account", so unrelated data lands in the same columns and the file is unreadable as a plain CSV.

Two more problems compound it: amounts are stored in cents with no decimal point (a $100,000.00 wire is 10000000), and credit/debit direction is not a field at all — it is encoded in the transaction type code (100–399 credit, 400–699 debit). This converter fixes all three issues and outputs a real, one-row-per-transaction CSV.

• UTF-8 BOM — the file opens with correct characters in Excel instead of showing mojibake on accented text.
• Comma or semicolon delimiter — use the semicolon download for European Excel locales that treat the comma as a decimal separator and would otherwise split every amount into two columns.
• Quoted fields — descriptions containing commas or line breaks are quoted per RFC 4180 so the column count never drifts.
• One row per transaction — 88 continuation records are merged into the description of the transaction they belong to, rather than becoming stray rows.

• 01 — File header: sender, receiver, creation date
• 02 — Group header: as-of date and currency
• 03 — Account identifier, plus opening/closing ledger and available balances
• 16 — Transaction detail: type code, amount, bank reference, customer reference, text
• 88 — Continuation: appended to the previous record so long descriptions stay intact
• 49 / 98 / 99 — Account, group and file trailers