GSRN Check Digit Calculator

How GSRN Check Digit Calculator Works?

The GSRN Check Digit Calculator works by weighting the 17 payload digits of a Global Service Relation Number (GSRN) 3-1-3-1 from left to right and appending the 18th digit.

1. 1Combine the GS1 company prefix with the service reference to reach 17 digits.
2. 2Multiply the 9 odd-position service digits by 3 and the 8 even-position digits by 1.
3. 3Total the 17 products and take (10 − (S mod 10)) mod 10 as digit 18.
4. 4Encode with AI (8017) for a service provider or AI (8018) for a service recipient.

GSRN Check Digit Calculator Formula

The GSRN formula is d₁₈ = (10 − ((3 × odd-position sum + even-position sum) mod 10)) mod 10.

S = 3 × (d₁ + d₃ + … + d₁₇) + (d₂ + d₄ + … + d₁₆)   (GSRN)
d₁₈ = (10 − (S mod 10)) mod 10   (GSRN)

• d₁…d₁₇ are the 17 GSRN payload digits (company prefix + service reference).
• d₁₈ is the GSRN check digit.
• S is the weighted GSRN sum.

Payload:  12345678901234567
Weights:  31313131313131313
S = 155
Check digit = (10 − (155 mod 10)) mod 10 = 5
GSRN = 123456789012345675

GSRN Check Digit Calculator Conversion Table

The GSRN conversion table shows service relationships with their payload, check digit, and Application Identifier.

What is GSRN Check Digit Calculator?

A GSRN Check Digit Calculator is a tool that completes the 18-digit Global Service Relation Number used to identify the relationship between a service provider and a service recipient.

Hospitals use GSRNs on patient wristbands and caregiver badges, and loyalty schemes use GSRNs on member cards.

What are the uses of GSRN Check Digit Calculator?

There are 3 main uses of the GSRN Check Digit Calculator, including patient wristbands, staff badges, and loyalty cards.

• Patient wristbands: Hospitals encode patient GSRNs with AI (8018).
• Staff badges: Care providers identify caregivers with AI (8017).
• Loyalty cards: Retailers number member cards with a GS1 check digit.