UK NHS Number Generator
UKGenerate valid-format NHS numbers with correct check digits using the Modulus 11 algorithm. NHS numbers are 10-digit identifiers used throughout the UK healthcare system.
Generator
Validate NHS Number
NHS Number Format
Length: 10 digits
Format: 3-3-4 when displayed
Check digit: Modulus 11 (last digit)
Valid check digits: 0-9 (not 10)
Modulus 11 Algorithm
- Multiply each of first 9 digits by weight (10 to 2)
- Sum the products
- Divide by 11, take remainder
- Subtract from 11 to get check digit
- If result is 11, check digit is 0
What is This Tool?
A NHS number generator creates fictional 10-digit NHS numbers with valid check digits using the Modulus 11 algorithm. NHS numbers uniquely identify patients across all NHS services in England, Wales, and the Isle of Man, and are essential for healthcare software testing.
NHS numbers use a weighted Modulus 11 checksum: each of the first 9 digits is multiplied by a descending weight (10 down to 2), summed, and the remainder from dividing by 11 determines the check digit. If the remainder is 10, the number is invalid and must be regenerated.
Common Use Cases
Healthcare Software Testing
Test patient registration, electronic health records (EHR), and clinical systems with valid-format NHS numbers.
NHS Spine Integration
Validate Personal Demographics Service (PDS) lookups and NHS Spine integrations in healthcare applications.
GP Practice Systems
Test appointment booking, prescription management, and patient record systems used by GP practices.
Health Data Anonymization
Replace real NHS numbers with fictional ones when creating anonymized datasets for research and testing.
Frequently Asked Questions
Are generated NHS numbers real patients?
No. Numbers have valid check digits but are not registered with NHS Digital and do not correspond to any real patient.
How is the check digit calculated?
Multiply digits 1-9 by weights 10-2, sum the products, divide by 11. The check digit is 11 minus the remainder (if 10, the number is invalid; if 11, the check digit is 0).
Are Scottish CHI numbers supported?
This generator produces standard 10-digit NHS numbers used in England and Wales. Scottish CHI numbers follow a different format.