Guides
Half the job is knowing where the number lives in the first place. These cover that, and are honest about when you do not need a tool at all.
Utility meters
How to Read My Electric Meter From a Photo
How to read my electric meter correctly from a photo: which digits count, why red numbers are ignored, dial meters, Economy 7 rows, and where OCR trips up.
Water Meter OCR: Reading a Meter From a Photo
Water meter OCR is harder than it looks: fogged glass, red sweep hands and odometer digits mid-roll. What to photograph, and which digits actually get reported.
Numbers
Decimal Separator: 1,234.56 or 1.234,56?
The decimal separator is a comma across most of Europe and a point in the US. Same quantity, two spellings, and a scanner that guesses wrong moves the value.
Extract Phone Numbers From an Image or Photo
Extract phone numbers from an image: the free tools that already do it, the numbering rules that catch misreads, and how to clean the list before you dial.
Image to Excel: the Traps in Data From Picture
Image to Excel works well until a long number appears. Excel's Data from Picture, the 15-digit ceiling, lost leading zeros, and how to avoid each of them.
OCR Accuracy: Why Numbers Come Out Wrong
OCR accuracy is quoted per character, which hides the real problem. On a long number the whole string is what matters, and that falls away fast. Here is the maths.