This is a free online Luhn algorithm (mod 10) validation tool that runs entirely in your browser. You can validate credit card numbers, IMEI numbers, ISBNs, and other Luhn-protected numbers, generate check digits, and batch validate multiple numbers. No data is ever uploaded to a server.
When developing payment systems, validate test card numbers or generate Luhn-compliant test card numbers.
Batch validate card numbers or IMEI numbers in a database to quickly filter out invalid entries.
Verify that stored identification numbers have correct format, ensuring data integrity.
The Luhn algorithm was invented by IBM scientist Hans Peter Luhn in 1954. Steps: from right to left, double every second digit; if the product exceeds 9, subtract 9; sum all digits; if the total is divisible by 10, the number is valid. The algorithm detects all single-digit errors and most adjacent digit transpositions, but not certain specific double-digit swaps.
A simple checksum algorithm invented by Hans Peter Luhn in 1954, used to validate identification numbers by detecting common errors.
All numbers using Luhn: credit cards, IMEI, Canadian SIN, NPI, etc.
Enter digits without the check digit, and the tool calculates and appends the correct Luhn check digit. Useful for development testing.
Absolutely not. All calculations run locally in your browser. No data is ever sent to any server.
No. It detects all single-digit errors and most adjacent transpositions, but not certain double-digit swaps.
One per line, recommended max 1000 per batch for browser performance.