A QBO bank download isn't a QuickBooks company file
It's easy to assume a .qbo file requires QuickBooks because of the name, but a QBO bank download is actually an OFX-based Web Connect file — the same underlying structure used by OFX and QFX exports. It's built for QuickBooks to import, but it doesn't require QuickBooks to read. It's a plain, structured text file describing a set of bank or credit-card transactions.
That's a different thing from a QuickBooks company file (.qbw) or a company backup (.qbb), which store an entire set of accounting records — accounts, invoices, settings — built by the QuickBooks application itself. A .qbo bank download only contains transaction data for one statement period, not a company's books.
What's inside a QBO file
Structurally, a QBO file follows the same OFX-family layout as .ofx and .qfx exports: an account section identifying the bank and account, followed by a list of transactions with posting dates, amounts and descriptions, and usually a running or ending balance. Bank and credit-card downloads are the common case; QBO files aren't used for full accounting exports.
Inspecting it without QuickBooks or a login
Because it's just structured text, you can convert a .qbo file into a CSV or Excel spreadsheet without installing QuickBooks, creating a QuickBooks Online account, or connecting to your bank a second time. The conversion reads the same transaction fields QuickBooks would import — dates, amounts, payees and available check numbers — and lays them out as spreadsheet rows.
Bankfile's QBO converters do this locally in your browser, so no QuickBooks login or account connection is involved at any point — you're just reading the file you already have.
What gets preserved, and what doesn't
A conversion keeps the transaction-level detail QuickBooks itself would use: posting dates, exact amounts, payee text, and transaction IDs or check numbers where the bank included them. What it deliberately doesn't produce is a QuickBooks import mapping or category assignment — QBO files aren't structured to carry that, since categorization normally happens inside QuickBooks after import, not in the bank's export.