Upload a customer, supplier or contact list and this checks it against the things that actually break UK business systems: postcodes that do not exist, VAT numbers that fail HMRC's checksum, company numbers Excel has stripped the leading zero from, and dates nobody can read the same way twice.
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What gets checked
UK postcodes
Flags values that are not a real postcode format, and mixed spacing that stops records matching between systems.
VAT numbers
Runs HMRC’s mod-97 checksum, not just a length check. Catches transposed digits that look fine but get rejected.
Company numbers
Finds numbers where Excel has stripped the leading zero — the single most common cause of failed Companies House lookups.
Dates
Detects columns holding both day-first and month-first dates, which silently corrupts every ageing report built on them.
Duplicates
Exact duplicate rows, and the same email address appearing across several different records.
Emails and phones
Invalid formats, throwaway domains, and numbers that have lost their leading zero.