00/Powered by Claude and Jev
Books your CPA won’t have to fix.
Accounting software built by a licensed CPA. Connect your bank, press Auto-Categorize and confirm what it found. Every entry posts balanced, so your statements are right the first time.
Built and run by a licensed CPA.
FIG. 01Transactions · after Auto-Categorize
Transactions
Bank activity, and what the books made of it.
Needs matching
1Transfers between accounts
1The same money leaving one account and arriving in another.
Checking (...4821)
TRANSFER TO SAVINGS ...4822
Savings (...4822)
TRANSFER FROM CHECKING ...4821
Review queue
4 ready to post
CategoryFinalize | Actions | ||||
|---|---|---|---|---|---|
Sep 18 | POS PURCHASE STORE 214 Checking (...4821) | -$186.00 | |||
Sep 12 | TRANSFER FROM CHECKING ...4821Pair Savings (...4822) | $600.00 | Transfer | ||
Sep 12 | TRANSFER TO SAVINGS ...4822Pair Checking (...4821) | -$600.00 | Transfer | ||
Sep 9 | INSURANCE PREMIUM Checking (...4821) | -$120.00 | |||
Sep 5 | SOFTWARE SUBSCRIPTION Checking (...4821) | -$79.00 | |||
Sep 2 | ACH CREDIT INVOICE 1042 Checking (...4821) | $2,400.00 |
Ledger
Double-entry enforced in the database
Integrity
Entries that do not balance do not post
History
A full audit trail on every change
Operator
Built and operated by a licensed CPA
02/Claude and Jev
Press Auto-Categorize. Claude and Jev do the reading.
Your rules run first. Whatever they leave, Claude reads — the memo, the merchant, the amount — and Jev, the judgment model inside 42six, picks the account in your chart it belongs to, and only records a pick when it is confident.
It runs when you ask, not behind your back. Every pick waits for you to finalize, and anything you change can become a rule that handles the case from then on.
- You pressAuto-Categorize
- Your rulestake what they know
- Claude readsmemo, merchant, amount
- Jev placesthe account in your chart
- You finalizeand it posts balanced
You press the button
Claude and Jev read nothing until you click Auto-Categorize.
Rules, then AI
Your rules always win. Claude and Jev only see what they leave.
You finalize
Picks wait for you. Posting is always your call.
03/How it works
Take the tour.
September at a sample studio, page by page, in the screens you would actually use. Pick a page, then step through it at your own pace.
1 / 4Transactions arrive. The month’s lines land in Transactions. The transfer is already up top in Needs matching.
Transactions
Bank activity, and what the books made of it.
Needs matching · nothing right now
Review queue
0 ready to post
CategoryFinalize | Actions | ||||
|---|---|---|---|---|---|
Sep 2 | ACH CREDIT INVOICE 1042 Checking (...4821) | $2,400.00 |
04/In the product
Everything the books need. Nothing they do not.
Claude and Jev
Auto-Categorize reads every line your rules miss and places the ones it is sure of in your chart. The rest wait for you.
MCP server
Connect Claude or ChatGPT to your books and ask about them in plain language.
Multiple entities
Every business its own set of books, each with its own chart.
Rental properties
Each property its own book, on a chart built for rentals.
- Bank connectionsTransactions sync on their own.
- RulesCategorize by memo, direction and account.
- Transfer matchingMoves between your accounts, waiting to confirm.
- ReconciliationTie each account to its statement.
- Period locksA closed month stays closed.
- Financial statementsProfit and loss, balance sheet, trial balance.
- ExportCSV and Excel, whenever you want.
- API keysKeys you create and revoke yourself.
05/The difference
Bookkeeping used to be a chore you caught up on.
− The old way
+ With 42six
−The old way: A shoebox of transactions, sorted in a weekend every quarter.
+With 42six: One click. Your rules first, then Claude and Jev for whatever they miss.01
−The old way: An entry can be wrong and still save.
+With 42six: An entry a cent out is refused when it commits. It never becomes a row.02
−The old way: Opening Balance Equity sitting on your balance sheet in front of your banker.
+With 42six: No Opening Balance Equity, ever. Opening balances post to Retained Earnings.03
−The old way: Transfers between your own accounts booked as income and expense.
+With 42six: A move to savings is recognized as a transfer and posts as one entry.04
−The old way: Books held hostage by the software that keeps them.
+With 42six: Export your ledger, reports and chart of accounts to CSV or Excel any time.05
06/What you get
Books you can hand to anyone.
SPEC / 06.1
A month in one click
Auto-Categorize places what it is sure of and leaves the rest for you, so catching up takes minutes, not a weekend.
SPEC / 06.2
Balanced by construction
The database refuses an unbalanced entry. There is no tolerance setting.
SPEC / 06.3
Closed means closed
Lock a period and every entry in it stays exactly as you reconciled it.
SPEC / 06.4
Yours to take
Your ledger, reports and chart export whenever you want them.
07/Proof you can check
One cent out. Refused.
Here is the September software subscription with its credit a penny short. A check in the database sums every line when the transaction commits; if debits and credits disagree by any amount, the entry never becomes a row. It is not a warning or a task for later.
| Account | Memo | Debit | Credit |
|---|---|---|---|
| 713000 Office Expenses & Software | 79.00 | — | |
| 100100 Checking (...4821) | — | 78.99 | |
| Out of balance by 0.01 | 79.00 | 78.99 | |
08/Why 42six exists
Built by a CPA who was tired of fixing books.
Tim LeGendre is a licensed CPA. Forty Two Six is the accounting engine his own firm keeps clients’ books on, opened up so any owner can run it.
It is built the way an accountant would insist: double-entry enforced where it cannot be skipped, no Opening Balance Equity, a trail behind every change, and books that leave with you whenever you want them to.
Tim LeGendre, CPA
09/Pricing
Run it yourself, or have Tim run it.
Core and Pro have every feature. Core holds one business book and one Personal book; Pro holds as many as you need. Managed is Tim operating your books for you.
Core
$35USD /mo
One set of books, kept honestly.
Everything the ledger is:
- Double-entry enforced in the database
- The six invariants, on every entry
- Full audit trail
- One entity
- Profit and loss
Enough to keep one small set of books properly.
Pro
$100USD /mo
The whole product, and the ledger is yours.
Everything in Core, and:
- Unlimited entities
- CSV export of everything
Managed
RecommendedStarting at$350USD /mo
We do it all for you.
Talk to TimEverything in Pro, and:
- Your bookkeeping performed by a licensed CPA
- A monthly close, done for you
- Each period locked once it is closed
- Requests, so nothing is chased over email
Pricing depends on volume and how many entities you keep.
[10] Security
Your books are evidence. We keep them that way.
Security · Spec
- S.01The ledger is guarded
- Your browser can read your books but never write them directly. Every change goes through a checked door.
- S.02Your books are yours alone
- Each workspace is isolated in the database, row by row.
- S.03Bank credentials encrypted
- Connection credentials are encrypted and never reach your browser.
- S.04Two-factor, your choice
- Turn it on and every sign-in asks for it before your books open.
- S.05A trail behind every change
- Who changed what, and when, is recorded on every edit.
- S.06Locked periods stay locked
- A closed month cannot be edited out from under you.
11/Questions
Asked often.
12/What’s next
Let the books keep themselves.
When sign-ups open, start with one business. Your ledger exports whenever you want it, because books you cannot take with you are not really yours.