GS1 Digital Link Resolver

The public gateway between QR codes and your DPP

When someone scans a QR code on your product, the request hits the GS1 Digital Link resolver. It is a publicly accessible service that resolves GS1 URIs — GTIN, GTIN plus serial number, GTIN plus batch — and returns the right response: a full JSON-LD DPP document for machine consumers, or a redirect to the product information page for humans.

One scan. The resolver decides what to serve.

Full GS1 Digital Link compliance

The resolver implements the GS1 Digital Link standard for URI resolution, supporting three identification patterns: /01/{gtin}, /01/{gtin}/21/{serial}, and /01/{gtin}/10/{lot}. Content negotiation determines the response. Request ?linkType=gs1:dpp or send an Accept: application/ld+json header, and you get the complete signed DPP document. Default requests receive an HTTP 302 redirect to the brand’s product information page.

Item Trace API

The resolver includes an Item Trace endpoint: GET /itemtrace?gtin={gtin}. It returns all 15 DPP data categories for a product in a single response — designed for complete product data export and integration with external systems such as market surveillance authorities, retail partners, or sustainability platforms.

Every scan is recorded

Every QR code scan captures rich telemetry: product identification, source and resolved URLs, response codes, IP geolocation (city, country, region, coordinates via IPInfo), and full device intelligence including browser, device type, operating system, and bot detection. All analytics are collected asynchronously with zero impact on scan response time. You see where your products are being scanned, on what devices, and whether the traffic is human or automated.

Why does a Digital Product Passport need a GS1 Digital Link resolver?

The EU’s Ecodesign for Sustainable Products Regulation (ESPR 2024/1781) requires that every product carries a data carrier — typically a QR code — that links to its Digital Product Passport. The CEN/CENELEC technical standard prEN 18220 specifies GS1 Digital Link as the format for that data carrier. A resolver is the service that sits behind the URI and decides what to return.

Without a resolver, a QR code is just a URL. With one, it becomes an intelligent gateway that can serve machine-readable JSON-LD to a market surveillance authority, redirect a consumer to a branded product page, or return structured data to a retail partner’s system — all from the same scan.

This is not optional infrastructure. It is the mechanism that makes your DPP accessible to every audience that needs it: regulators, consumers, supply chain partners, and sustainability platforms.

How does content negotiation work in practice?

Content negotiation is the process by which the resolver inspects the incoming request and decides what format to return. Two signals determine the response:

Query parameter: If the scan includes ?linkType=gs1:dpp, the resolver returns the full JSON-LD Digital Product Passport document, cryptographically signed if signing is configured. This is the format that market surveillance authorities and automated compliance systems expect.

HTTP Accept header: If the request includes Accept: application/ld+json, the resolver treats it the same as a gs1:dpp link type request and returns the structured DPP document.

Default behaviour: Any other request — which covers virtually all consumer QR code scans from a phone camera — receives an HTTP 302 redirect to your DPP product page. The consumer sees a branded, mobile-friendly page with product information, sustainability data, and material composition.

This means a single QR code serves both regulatory and consumer purposes. A compliance inspector scanning with a DPP verification tool receives machine-readable data. A shopper scanning with their phone camera lands on a page designed for humans. No separate codes, no separate infrastructure.

What identification patterns does the resolver support?

The GS1 Digital Link standard defines a URI structure that embeds product identification data directly in the path. Aura’s resolver supports three patterns:

• GTIN only — /01/{gtin} — identifies a product at model level. Suitable for products where every unit is identical and a single DPP covers the entire model range.
• GTIN plus serial number — /01/{gtin}/21/{serial} — identifies a specific individual item. Required for item-level DPPs where each unit has unique traceability data, such as batteries (mandatory from February 2027) or high-value electronics.
• GTIN plus batch/lot — /01/{gtin}/10/{lot} — identifies a production batch. Used when products within a batch share the same composition, supplier data, and manufacturing conditions but differ from other batches.

These patterns align with the three levels of Digital Product Passport defined in the ESPR: model-level, batch-level, and item-level. The resolver matches the URI pattern against your product catalogue and returns the correct DPP for that level of granularity.

For more on GS1 Digital Link as a standard, see our explainer on what GS1 Digital Link is and how it works.

What does the Item Trace API return?

The Item Trace endpoint (GET /itemtrace?gtin={gtin}) returns all 15 DPP data categories for a product in a single structured response. This is designed for system-to-system integration rather than QR code scanning.

Use cases include:

• Market surveillance authorities pulling complete product data for regulatory verification
• Retail partners integrating DPP data into their own product information systems
• Sustainability platforms aggregating DPP data across multiple brands for benchmarking or reporting
• Internal systems such as ERP or PLM platforms that need structured DPP data for downstream processes

The response includes composition, supply chain, transport, environmental data (Scope 1/2/3 carbon), certifications, circularity scores, and all other EPRS categories — everything that would appear in the full DPP data model.

How Aura helps

Setting up a GS1 Digital Link resolver typically requires a dedicated infrastructure project: domain provisioning, URI routing, content negotiation logic, analytics pipelines, and ongoing maintenance. With Aura, the resolver is provisioned automatically when you create your account. There is no infrastructure to configure, no servers to manage, and no standards documentation to interpret.

Your resolver is live from day one. Generate QR codes for your products, and every scan routes through the resolver to the correct DPP document or product page. Scan analytics flow into the reporting dashboard automatically. The compliance assessment tracks whether your products are properly linked. It is one connected pipeline, not a collection of disconnected tools.

Frequently asked questions

Do I need to understand GS1 standards to use the resolver?

No. Aura handles the GS1 Digital Link URI structure, content negotiation, and standards compliance automatically. You add products with GTINs, generate QR codes, and the resolver works. The technical detail matters for interoperability with regulators and supply chain partners, but you do not need to configure or manage it.

Can market surveillance authorities access my DPP data through the resolver?

Yes. When a market surveillance authority scans a product’s QR code with a DPP verification tool (requesting ?linkType=gs1:dpp), the resolver returns the full signed JSON-LD document. This is by design — the ESPR requires that DPP data be accessible to authorities. Consumer scans receive a redirect to the product page instead.

Does the resolver work with non-GTIN identifiers?

The resolver currently supports GTIN-based identification, which is the standard specified by GS1 and referenced in the CEN/CENELEC prEN 18219 technical standard for DPP unique identifiers. If your products do not yet have GTINs, the product data management section can help you assign them.

What happens if a product’s DPP data changes after QR codes are printed?

The QR code encodes a URI, not the data itself. When a product’s DPP is updated on the platform, the resolver automatically serves the latest version on the next scan. Printed QR codes do not need to be reprinted — the data behind them is always current.