How checking works
The checker compares amounts per account, not wording. It runs entirely in your browser, follows fixed rules, uses no AI, and gives the same entry the same result every time.
What is compared
Your entry is reduced to its net effect on each account. Every amount is counted in whole cents, debits as plus and credits as minus, and the lines of the same account are added up. An account whose lines cancel out drops out. The answer is reduced in the same way, and the two are compared.
- The order of the lines does not matter.
- Splitting does not matter. 300.00 and 200.00 debited to the same account count exactly like one line of 500.00.
- Correct means that every account ends with exactly the amount of an accepted answer, and that no other account appears.
- All arithmetic is done in whole cents, never with rounded decimals.
Accepted variants
Some transactions have more than one legitimate presentation within the same convention. When an item accepts more than one, each is stored as an accepted answer: your entry is correct if it matches any of them, and the answer panel shows them under "Also accepted". When your entry matches none, the feedback compares it with the accepted answer it is closest to, the one with the fewest differences.
What the feedback can say
When an entry is not correct, the feedback lists only what follows from comparing it with the answer:
- Unbalanced: debits minus credits equals a given amount. This is always listed first, even when other things are wrong too.
- Missing account: an account of the answer is not in your entry.
- Extra account: an account in your entry does not belong in this entry.
- Wrong side: the account belongs in the entry, but on the other side. The feedback also says whether its amount is different.
- Wrong amount: right account, right side, but the amount is too high or too low by a given amount. The expected amount itself is not shown.
- Wrong account type (a hint): when an extra account carries exactly the amount of a missing account, and the two belong to types that are often confused (an asset and an expense, or a liability and revenue), the feedback points this out in addition to listing both. It appears only when no other account carries that same amount.
Named slips
A few common slips get a name, but only when your whole entry equals the answer changed in exactly that way. Any other entry, however close, gets the plain list of differences above.
- VAT missing: the VAT (or sales tax) line is missing, and an account on the other side is lower by exactly the tax amount.
- VAT included: the tax line is missing, and an account on the same side is higher by exactly the tax amount, as when an expense is recorded at the gross amount.
- Split swapped: the amounts of two accounts on the same side are exchanged.
- Every side reversed: every account and amount is right, but each one is on the opposite side.
Automated tests check, for every item and convention, that none of these names fires on thousands of other mistakes.
What the checker never does
- It gives no score, percentage or partial credit: an entry is correct or it is not, with the list of differences.
- It never guesses what you meant and never judges your accounting policy. Each item states its assumptions above the columns, such as the inventory system, the VAT rate or how depreciation is recorded, and the answer follows from them.
- It does not show the answer before you ask: the worked answer appears after a correct entry or when you choose "Show answer".
Conventions are a setting, not a language
The convention decides the chart of accounts, the account names and codes, the inventory system, the VAT accounts and which answer an item expects. The page language decides only the language of the interface and of the transaction. Each language starts with its own convention, and you can switch above any entry; your choice is remembered in your browser.
| Convention | Inventory | VAT | Accounts |
|---|---|---|---|
| United States (US textbooks) | Perpetual: each sale also records its cost of goods sold | None; sales tax where an item says so | US textbook names |
| Spain (PGC 2007) | Periodic: purchases in 600, sales in 700 | 21%: 472 and 477 | PGC names and codes |
| France (PCG 2025) | Periodic: purchases in 607, sales in 707 | 20%: 44566 and 44571 (44562 on fixed assets) | PCG names and codes |
| Germany (generic accounts) | Purchases of goods recorded as an expense (aufwandsorientiert), unless the item says otherwise | 19%: Vorsteuer and Umsatzsteuer | Generic German names, no SKR numbers |
Account names stay in the convention's own language whatever the page language: on an English page with the Spanish convention you see "472 Hacienda Pública, IVA soportado". Amounts are shown in US dollars for the US convention and in euros for the others. An item with no equivalent in a convention says so and asks you to choose another one.
Typing amounts
Type amounts the way you write them, for example 1,234.56, with up to two decimals; a currency sign is ignored. An amount that could be read two ways, zero, a negative amount or more than two decimals is refused with a message next to the field, and nothing is checked until every amount can be read.
Reporting a disputed answer
Under every entry there is a report reference: the item, its revision, the convention and the number of the set of amounts ("New amounts" draws a new set). It is enough to reproduce your entry exactly. If you believe a correct entry is marked wrong, please report it with that reference.