Check whether an invoice's line items add up
Fictional invoice · narrated explanation · English captions · about 94 seconds
A matching total can hide a line error. Work through a fictional invoice where four hours at USD 75.00 are printed as USD 375.00. Download the example PDF and calculated answer, then compare what the checker reads. Educational calculation; this video does not demonstrate a live OCR run. The standalone checker does not verify agreed rates or delivery.
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1. A matching total can hide a line error
This invoice totals five hundred dollars. Its printed line amounts add up to that total. But one line is still wrong. Four hours at seventy five dollars should be three hundred dollars. The supplier has printed three hundred seventy five. A matching grand total alone would miss the seventy five dollar difference.
2. Read the line before changing it
Start with quantity times unit price. Then compare that result with the amount printed on the line. Here the extra administration charge is one hundred twenty five dollars. The two printed amounts sum to five hundred. That explains why the subtotal agrees even though the service line does not. Ask the supplier to confirm the charge before changing your records.
3. Compare the reading with the source
You can download this fictional invoice and its calculated answer from the linked worked example. Upload the PDF in the invoice math checker and compare the reading with the source. These numbers are an educational expectation, not a recorded extraction result. If a figure is misread or unchecked, it still needs your attention.
4. Check the next invoice
The standalone checker compares an invoice with itself. It cannot establish that the hourly rate was agreed or that the work happened. Once you understand the example, try a document from your own workflow. The browser tool allows up to three documents a day, subject to shared limits, without signup.
Published October 11, 2026. Synthetic educational material with text-to-speech narration. Calculated expectations; live extraction and accounting posting are not shown.