All tools · page 237

Computes and verifies Luhn mod-10 check digits for card and account numbers.

Computes the 15th Luhn digit for IMEI bodies.

Computes the North American VIN check digit with transliteration weights.

Builds LPA:1$SMDP$ACTIVATION_CODE carrier strings for eSIM install codes.

Converts a CSV of network credentials into one WIFI: string per row for IT rollouts.

Builds pre-filled form entry URLs from field IDs and values for scannable feedback codes.

Validates 13-digit structure, prefix ranges, and check digits of EAN-13 codes.

Validates EAN-8 digit counts and check characters before label printing.

Validates UPC-A number system, manufacturer, product, and check structure.

Expands 8-digit UPC-E back to UPC-A and recompresses with zero-suppression parity rules.

Validates Code 39 character set, start and stop asterisks, and length limits.

Validates Code 128 start patterns, check character, and stop bar structure.

Validates even digit counts and optional mod-10 checks for ITF pairs.

Validates ITF-14 indicator digit, GTIN-14 body, and check digit.

Validates Codabar digits, ABCD start and stop pairs, and optional checksums.

Converts legacy ISBN-10 to ISBN-13 with a 978 prefix and recomputed check digit.

Explains registration-group and registrant split rules for hyphenating ISBNs.

Maps GS1 company-prefix ranges to member organizations by country.

Pads UPC-A values into GTIN-14 carton codes with indicator digits.

Explains indicator digits 1-8 and 9 for carton hierarchy levels.

Converts FDA NDC 5-4-2 codes into GTIN-14 retail codes.

Strips dashes and spaces from GTINs and reports length and type.

Prepends the 977 prefix and issue number to ISSNs for serial barcode conversion.

Maps number system and six digits to odd-even parity patterns for UPC-E structures.