Same text, different calendar day
12/10/2026 → DMY: 2026-10-12 · MDY: 2026-12-10
Both orders are valid. A successfully parsed date does not establish the intended order. Check the source format; Australian location alone is not used to guess it.
Australian invoice templates · repeat-client date review
Did your invoice template keep the same dates?
Check confirmed invoice dates against spreadsheet or CSV output. Review slash-date ambiguity and workbook serial shifts before reusing a template for repeat clients.
Try the invoice tool now ↗When a new invoice is appropriate, manually enter verified details in the existing tool. Start without signing in; free output has branding and usage limits. Existing saving, membership and PDF/image export capabilities apply. This checker adds no automatic invoicing feature.
Try a filled fictional transfer example
Use internal codes, not customer or banking data. Entries are processed on this page without uploading them or saving them to an account, draft or invoice history. The fixed example is not your result.
Select Check dates to review the current inputs.
Four transfer cases worth checking
Different text, same calendar day
13/10/2026 → DMY: 2026-10-13
Start with an independently confirmed ISO date. Interpret the transferred value using its explicit format. The comparison uses calendar days, so a formatting change alone is not an error.
Workbook date-system mismatch
2008-01-01 → Excel 1900: 39448 · Excel 1904: 37986
The integer serials for the same day differ by 1462. Verify the actual workbook setting rather than inferring a date system from the computer model.
Invalid dates stay unresolved
31/02/2026 → unresolved / 未确定
31 February is not rolled into March. Two-digit years, serials containing time fractions and the fictitious 1900-system serial 60 are not accepted.
The default DMY case should show 2 same-day records, 1 different and 1 unresolved. ROW-B becomes 2026-05-10, 148 days before confirmed 2026-10-05. Even a same-day result retains a warning when both slash orders are valid.
Download the fictional input and worked explanation TXT · Download the complete DMY example result JSON
A repeatable check before reusing a template
- Independently verify the intended date from the agreement, service record or approved document. Enter it as YYYY-MM-DD; this resource does not calculate a due date.
- Confirm column interpretation and the date system in the source workbook. A CSV does not retain all Excel workbook formatting and can be interpreted again when opened.
- Review one source representation at a time. Select DMY, MDY or the confirmed workbook system. If it is unknown, choose the unconfirmed option; no date is guessed.
- Enter an internal record code, the confirmed ISO date and the exported value. Use codes for multiple clients; do not enter names, banking information or private invoice content.
- Review differences and unresolved rows in the original workbook. Re-export and check again. Do not automatically overwrite issued invoices or alter agreed payment terms.
The checker interprets each entered date and compares it with its confirmed day. It does not group records by amount, customer or month, or recalculate an invoice.
Use 1–300 rows with unique internal codes. Confirmed dates must be valid years 1900–9999. This compares days, not times or time zones. Time fractions are not silently discarded. A 1462-day difference is a clue to review workbook systems, not a proven cause. This page does not open Excel files, parse PDFs, sync an account, generate recurring invoices or send bills.
Continue with the existing template and invoice tool
If you simply need to fill an Australian invoice, use the existing template entry. When choosing between an invoice and a tax invoice, verify your circumstances and official guidance. This date checker makes no tax determination.
Try the invoice tool now ↗Before using a result
Does a different display always mean the date is wrong?
No. With a confirmed DMY order, 12/10/2026 and 2026-10-12 represent the same day. Confirm the source representation before comparing calendar dates. This checker does not edit a workbook.
Does a match prove that an invoice date or payment term is correct?
No. A match only means the entered representations describe the same day. Independently verify the original date. This does not establish contractual due dates, tax dates or payment status, and does not read PDFs, accounts or drafts.
Sources and method
Microsoft documents date interpretation during CSV import and offsets between workbook date systems. ABN Invoice independently prepared this review method and the fictional examples. The sources do not endorse this tool. Conversion uses an explicit representation and strict Gregorian dates; two-digit years are not guessed.
- Microsoft: importing and exporting text/CSV
- Microsoft: workbook date systems
- business.gov.au: invoice information and record keeping
Reviewed 17 October 2026. A review or sample download is not an invoice, receipt or evidence of payment.