What checksum validation does
Before every export, Datamolino runs a checksum - a quick sense check to confirm that the amounts in your document add up consistently and match what will be sent to your accounting software. It is an automatic accuracy guard that catches data capture errors before they reach your books.
👉 Is the checksum the same for all document views?
Datamolino uses two types of checksum:
The Line items and Tax summary checksum verifies that your items or tax lines add up to the Invoice Total. When Validate totals is enabled and there is a mismatch, export is blocked - this stops a breakdown that does not reconcile from being sent to your accounting software.
The Invoice Total checksum compares the captured invoice amounts against what will actually be exported, based on your selected tax code. Any difference shows in red in the document view, but it never blocks export. It is informational - a prompt to check your tax code, not a requirement before you can proceed.
Resolving a mismatch
👉 What should I do first when I see a checksum mismatch?
For Line items and Tax summary mismatches, you have three main options:
Start with the tax code. In most cases, selecting the right tax code is all it takes to clear the mismatch - no amount editing needed.
Correct the Invoice Total. If the line items are right but the Invoice Total was captured incorrectly, update the Invoice Total at the document level. You only need to correct the figure being exported - NET or TOTAL, whichever is shown in bold.
Edit the amounts directly.You can edit the NET or TOTAL values to match the invoice. You can also try switching the Export Amount between Net and Total - this changes which figure Datamolino exports.
Use Add Adjustment Line for Line items. If the mismatch is a small rounding difference on NET or TOTAL, click Add Adjustment Line. Datamolino calculates the exact difference and adds a balancing line automatically. For details, see Rounding differences: why amounts don't match and how to fix it
Line items and Tax summary: the export blocking check
When your document uses Line items or Tax summary as the export format, Datamolino checks that the items or tax lines add up to the Invoice Total. This is the check that can block your export.
👉 Which figures does Datamolino compare?
Datamolino compares the amounts that are actually being exported, not every value on the document. Only NET or TOTAL is sent to your accounting software - whichever is shown in bold in the document view. For Xero documents set to Send exact tax amount, Datamolino also exports the exact tax amount alongside it. The checksum compares those figures to the equivalent NET or TOTAL on the Invoice Total. When the document is in Tax Summary view, the check sums the tax lines instead of the item lines.
👉 When does a mismatch block my export?
If Validate totals is enabled for the document and the figures do not reconcile, export is blocked. The document moves to Export error status and stays there until you correct the amounts or turn validation off for that document.
👉 Does this affect Auto export too?
Yes. If Auto export is enabled and a document has an unresolved checksum mismatch, Datamolino does not push it through automatically. The document stays in Export error until you correct the amounts or turn validation off for that document.
Invoice Total: the accuracy indicator
The Invoice Total checksum compares the captured invoice amounts against what will actually be exported, based on your selected tax code.
👉 What does a red indicator on Invoice Total mean?
A red indicator means Datamolino's recalculated figure - based on your selected tax code - does not match the Invoice Total captured from the document. It is a prompt to double-check that the right tax code is applied, not a signal that your export has been blocked.
👉 Does the red indicator stop me from exporting?
No. The Invoice Total checksum is informational only. You will see the difference highlighted in red in the document view, but you can still proceed with export. If the mismatch is small and you are confident the tax code is correct, no action is needed.
How the rules differ by accounting software
The checksum concept is the same across integrations, but each accounting software applies slightly different tolerances for small differences. Understanding your integration's rules helps you know when a minor rounding gap will be accepted automatically and when it needs correcting.
👉 How does Xero checksum validation work?
Xero requires the Invoice Total to match exactly. For tax, the strictness depends on your Xero tax setting:
Let Xero calculate tax (default): Datamolino sends the NET or TOTAL and lets Xero calculate the tax from the tax code. A small tax difference of up to 0.10 is tolerated automatically, because minor rounding from Xero's own calculation is expected. The TOTAL must still match exactly.
Send exact tax amount: Datamolino sends both NET and TAX, and Xero accepts them as-is. No tolerance applies - TAX and TOTAL must both match exactly, or the export is blocked.
For details on which Xero tax setting to use and when, see Tax calculation in Xero: automatic vs. exact amount.
👉 How does QuickBooks checksum validation work?
For non-US QuickBooks accounts (VAT-based), Datamolino checks net and tax separately. Differences of up to 0.10 on either are treated as acceptable rounding. The overall total still needs to add up consistently.
For US QuickBooks accounts, sales tax is handled by QuickBooks itself, so Datamolino does not apply a separate tax tolerance. Instead it checks whether the document subtotal (NET) or total matches the line items. There is no 0.10 buffer.
👉 How does the check work on a credit note?
Credit notes are validated using absolute values, because credit note amounts are often captured as negative but exported as positive. Datamolino compares the absolute subtotal, tax, and total figures - a sign difference on one line does not fail the check on its own, as long as the absolute totals reconcile.
If your mismatch is caused by a small rounding difference rather than a data capture error, see how Datamolino handles rounding differences for integration-specific options including adjustment lines.
Turning validation on or off
👉 Can I turn checksum validation off for a single document?
Yes. If the amounts on the document are intentionally how they are and you want to proceed with export, you can switch the validation off inside the document view.
To turn validation on/off for one document:
Open the document.
Open the validation settings from the document view.
👉 Can I turn validation off for all documents from one supplier?
Yes. Use Supplier Automation to disable validation automatically for all documents from a specific supplier. This is useful when a supplier's invoices regularly trigger the same small mismatch that you have already confirmed is intentional.
To turn validation on/off for the supplier:
Click 'Automation'
Switch Validate totals toggle.
Click Save changes.
👉 Should I leave validation on or off?
Leaving validation on is the safer default. The checksum catches data capture errors before they reach your accounting software, keeping your records consistent with the source document. Turning it off is best treated as a per-document or per-supplier exception, not a general folder-wide setting.