When people hear that LocoLedger works with AI, they often assume an AI reads their bank statements. It does not. The step that turns a PDF into a list of transactions involves no model at all. It is done with arithmetic, on your computer, before any AI is involved.
This post explains why it was built that way, how it works, and what arithmetic cannot check.
Why not let an AI read the statement?
A language model can read a statement, and most of the time it will get it right. The trouble is the rest of the time.
A model does not know when it is wrong. A misread amount comes back looking exactly as confident as a correct one. In most documents a small mistake is tolerable. In a bank statement, one wrong figure makes every total and every answer built on it wrong too, and nothing on the page tells you.
There is also a privacy reason. To read the statement, a model would need the whole document. LocoLedger’s design is that a connected AI never receives your actual documents, only the extracted details from the documents you allow. Reading the statement locally, without a model, is what makes that possible.
How it works
Your statement stays in one folder
When you add a statement, LocoLedger copies it into its folder and leaves your original exactly where it is. Everything that follows happens to that copy.
Finding the transactions
LocoLedger finds the table of transactions, with a date, a description and an amount on each line, and follows it across pages.
Checking the amounts add up
A bank statement carries a built-in check. Most print a running balance on every line, so each transaction has to take the previous balance to the next one.
LocoLedger checks every line this way: previous balance, plus or minus the amount, has to equal the balance printed on that line. A misread amount would break that sum on the line where it happened. A statement where every line adds up has been checked against the bank’s own figures.
A statement that does not add up, or has no running balance to check, waits for you instead. Nothing from it counts until you confirm it.
What arithmetic cannot check
Arithmetic proves the amounts. It cannot prove the descriptions.
A transaction’s description, such as the merchant’s name or a transfer reference, is text, not a number, so no total can confirm it. LocoLedger finds the description on each line, but finding text is not the same as reading it correctly. With a new bank’s statement, it is worth reading the rows once yourself.
It also needs a statement with text in it. A scanned page is a picture, and LocoLedger does not read pictures.
What happens after reading
A connected AI only sees your transactions if you allow it, and only at the level you choose. The five levels of what your AI can see goes through each one.
One limit, stated plainly: LocoLedger guards what your AI is sent, not what programs on your computer can open. Reading a statement locally keeps it away from the AI. It does not hide the file from other software on your machine.
Try it
LocoLedger runs on Windows 10 and 11. Download it, add a statement, and compare what it reads with the page.