Reconciliation difference finder
Open or type the bank reconciliation that does not balance, and add the book rows and the bank statement rows for the period. The page works out the difference, then runs the checks a bookkeeper runs by hand on every row: does the difference divide by 9 (two digits swapped), is a row equal to the difference, is a row half of it (a sign reversed), is an entry there twice. A row is listed only when the reconciliation, recomputed with that row corrected, comes to $0.00. The page reports what the numbers show.
Everything is worked out in your browser. Nothing typed or opened here is uploaded. The reconciliation in the form, typed or filled from a workbook, is kept as a draft in this browser's own storage until you clear the form; the book and statement rows are not kept at all. This page reads rows (.csv, .xlsx, or pasted). It does not read PDF files or scans.
A workbook made with the bank reconciliation template, or one downloaded from the bank reconciliation statement, fills in this whole step at once. Every figure can still be changed below.
The statement ending balance is the last balance on the bank statement; the book balance is the balance of the cash account in the ledger on the same date. The statement date is used to find outstanding items more than 90 days old.
Every amount on the four lists is typed as a positive number. On the bank corrections and book adjustments lists, Add or Subtract says which way a row goes.
Outstanding checks
| Check number | Date | Payee | Amount |
|---|
Deposits in transit
| Date | Description | Amount |
|---|
Bank corrections
| Description | Add or subtract | Amount |
|---|
Book adjustments
| Description | Add or subtract | Amount |
|---|
Or paste rows with a header row first (for example Date, Description, Debit, Credit):
The columns are matched from the header words; check them. In a ledger export of the cash account a debit is money in and a credit is money out, so a Debit column is matched to money in here. A check register's Payment and Deposit columns are money out and money in.
Or paste rows with a header row first (for example Date, Description, Amount):
The columns are matched from the header words; check them. On a bank export a debit or withdrawal is money out and a credit or deposit is money in.
Both row files are optional. Without the book rows, rows inside the book balance cannot be pointed at; without the statement rows, book rows are compared with the outstanding lists only. The rows are read in this browser and are not uploaded or kept.
The search runs once the statement ending balance and the book balance are both typed.
Candidates
Outstanding for more than 90 days
A candidate is a row that, corrected one way, makes the arithmetic balance. This page says what the numbers show. It makes no statement about which entry belongs in the books.
What gets checked
- The difference is the adjusted bank balance minus the adjusted book balance, worked out once from the totals and a second time row by row. The two must agree to the cent.
- Every candidate shown, applied to the reconciliation, recomputes it to a difference of $0.00: the balance or amount replaced, the row taken off its list or moved to the other list, the book row corrected inside the book balance, or the statement row put on the book side.
- Nothing is invented: every candidate points at a row that was given, with the amount it was given, and a swap is two neighbouring digits of that amount.
- A book row or a statement row is a candidate only when the other side holds its amount fewer times. A row with a partner is matched and is never named.
- A second search, made a different way (place values instead of text, sorted lists instead of counts), finds the same candidates and no others.
- Whether the difference divides by 9, and half of it, are stated exactly.
- A warning, not a candidate: an outstanding check or deposit in transit dated more than 90 days before the statement date.
- When files are opened: every row with data in the book and statement files was read, and every filled row of a template workbook was read.
How it works
- Enter the reconciliation. Open a workbook made with the bank reconciliation template, or one downloaded from the bank reconciliation statement, or type the statement date, the statement ending balance, the book balance, and the four lists.
- Add the book and statement rows. Drop or paste the book rows of the cash account and the bank statement rows for the period (.csv or .xlsx), and check the columns. In a ledger export of the cash account a debit is money in and a credit is money out, so a Debit column is matched to money in. Either file may be left out; the search then covers the rows it has.
- Read the candidates. Each candidate says which kind it is, which row it points at, and what the numbers show, such as this row's digits, swapped, would make the difference. Each one was recomputed to a difference of $0.00 before it was shown.
- Look at the old items, print or export. Outstanding items dated more than 90 days before the statement date are listed apart, as items to look at. Download Excel or CSV with the reconciliation, the candidates, the old items, and the certificate, or print the page.
Worked example
A made-up checking account for Example Supply Co. as of April 30, 2026. The reconciliation is off by $27.00. Opened with it are the eight book rows and the seven bank statement rows for April.
| Line | How it is built | Amount |
|---|---|---|
| Statement ending balance | From the April statement | $9,846.20 |
| Plus deposits in transit | Counter sales deposit 1,180.00 | $1,180.00 |
| Less outstanding checks | No. 3107 412.60 + No. 3110 86.40 + No. 2984 150.00 | -$649.00 |
| Plus bank corrections added | None | $0.00 |
| Less bank corrections subtracted | None | $0.00 |
| Adjusted bank balance | 9,846.20 + 1,180.00 − 649.00 | $10,377.20 |
| Book balance | From the cash account in the ledger | $10,360.05 |
| Plus book adjustments added | Interest 2.15 | $2.15 |
| Less book adjustments subtracted | Service fee 12.00 | -$12.00 |
| Adjusted book balance | 10,360.05 + 2.15 − 12.00 | $10,350.20 |
| Difference: adjusted bank − adjusted book | 10,377.20 − 10,350.20 | $27.00 |
| Difference ÷ 9 | 27.00 divides by 9, so two swapped digits can make it | $3.00 |
| Half the difference | No row moves the difference by 13.50 | $13.50 |
| Book row 3: check 3102 | In the books as 152.00 paid out; its 5 and 2 swapped read 125.00, the amount on statement row 3 | -$152.00 |
| Difference with -125.00 on book row 3 | 10,377.20 − 10,377.20 | $0.00 |
One candidate: book row 3, check 3102 to Example Office Supply, holds -$152.00, and statement row 3 holds -$125.00, with no partner on the book side. Its 5 and 2 swapped make exactly the $27.00 difference: with -$125.00 on book row 3, the book balance is $10,387.05, the adjusted book balance is $10,377.20, and the recomputed difference is $0.00. Outstanding check No. 2984, dated 2026-01-15, is 105 days older than the statement date, so it is listed as an item to look at, with a warning on the certificate. It is not part of the answer.
The example uses made-up names and numbers.
Questions
Why does dividing by 9 matter?
Swapping two neighbouring digits changes an amount by 9 times a power of ten times the gap between the two digits: 152.00 written for 125.00 is off by 27.00, which is 9 × 3.00. So a difference that divides by 9 can come from a swap, and one that does not cannot. The page does not stop at the test: it swaps every neighbouring pair of digits in every row and lists only the swaps that bring the difference to $0.00.
What does half the difference, sign reversed, mean?
An amount entered the wrong way round moves the difference by twice the amount: once for the entry that is missing and once for the one that is there. A deposit of 50.00 entered in the books as money out makes a difference of 100.00. So the page looks for any row whose amount is half the difference and recomputes with its sign turned around, or with Add and Subtract swapped, or on the other of the outstanding checks and deposits in transit lists.
Why is a row with a partner never named?
A book row whose amount is also on the statement rows, or on the outstanding checks or deposits in transit lists, is on both sides. Only rows that the other side holds fewer times are searched. When a book row and a statement row are a swap of each other, the book row is listed and the statement row is named beside it, once.
Does a candidate mean that row is wrong?
No. A candidate is a row that, corrected one way, makes the arithmetic balance. Two different rows can both do it, and a row can do it by coincidence; every one is listed. The page says what the numbers show and makes no statement about which entry belongs in the books. It is not accounting advice.
What if nothing is found?
Then no single row, corrected in one of these four ways, brings the difference to $0.00. The difference may come from more than one row, from a row that is not in the lists or files given, or from a row of an earlier period, such as a check written last month that cleared this month. The certificate still verifies the difference and the search.
Why are old outstanding items listed apart?
An outstanding check or deposit in transit dated more than 90 days before the statement date is worth a look, but being on the list is what the list is for: it does not by itself make the difference. So it is listed as an item to look at, with a warning on the certificate, and never as a candidate.
Is anything I open uploaded?
No. The workbook and the row files are read in this browser tab and nothing is sent anywhere. The reconciliation in the form is kept as a draft in this browser only; the Clear the form button removes it. The book and statement rows are not kept.
This tool calculates and checks numbers. It is not legal, tax, or medical advice.
Watch it run
A recording of this tool run on a made-up example is on YouTube, titled "Bank reconciliation off by $27.00? Find the row that makes it".
The link opens YouTube, which is another site. This page loads nothing from it.
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