QSeq.app is live: print-true GS1 identities, and what they mean for the printing industry

A generator for identities, not just symbols

Today Meerv Inc. is making QSeq generally available. You can use it right now in any browser at qseq.app, and download the native macOS and Windows builds from the same page. The web app is written in Dart/Jaspr from the same `qseq_core` that drives the desktop apps, so a single core serves macOS, Windows and the web identically — an identity minted on any surface is byte-for-byte the same.

QSeq is a generator for Barcodes, QR Codes and Data Matrix codes, but its purpose is narrower and more useful than that sounds. It exists to make it trivial to mint correct, durable, standards-based identities for physical things — and to do it in a way that anyone can use, audit, and build on. The full rationale is in the QSeq README; the release-by-release detail is in the CHANGELOG. This post is the short version, and why it matters if you print.

The problem QSeq solves

Every object in a modern supply chain needs an identity a scanner can read and a server can resolve: a GTIN, a serialized SGTIN, or a web-resolvable GS1 Digital Link. Getting that right is fiddly, and four things have to be true at once:

Most tools get one or two of these right. QSeq is built to get all of them right at the same time.

The defining feature: a live physical-size calculator

QSeq's signature capability is a live outer-size readout. The printed outer perimeter is shown — in mm, inches and pixels at the target DPI — as a function of the centre logo dead-space, the byte count, the printing resolution, and the error-correction level. Change any input and the physical size updates live, so what you design on screen is exactly what comes off the press.

Four properties make that trustworthy:

What it means for the printing industry

For converters, label houses and flexographic printers collaborating with Meerv Inc., QSeq is the front end that mints the identities the rest of the stack depends on. It is built for the press:

Every sheet increments the serial, so no two printed codes name the same thing, and the serialization log accounts for every identifier minted — the audit trail a production run needs.

Why a serialized, web-resolvable identity — and where QDat.io fits

QSeq draws a sharp line that the printing industry should care about. A Stock Keeping Unit — or any bare, class-level GTIN — names a kind of thing, not a thing. Unserialized, it is shared by every unit in the batch and never resolves to a per-item record. Identity begins at serialization: an SGTIN carried in a web-resolvable GS1 Digital Link, where each physical item resolves to its own record.

That is the collaboration point with QDat.io, also a brand of Meerv Inc. QSeq lets you point each GS1 Digital Link at a resolver, and ships a built-in QDat.io preset that rewrites the domain to `tapdpp.qdat.io`. So a code minted on the press in QSeq resolves spatiotemporally on QDat.io's Digital Product Passport module — the same (When, What, Where) loop the TapDPP reader and the tapdpp.qdat.io playground demonstrate. QSeq mints the identity; QDat.io resolves it.

Sustainable Identity on Every Thing

QSeq is released source-available (PolyForm Noncommercial 1.0.0) in service of Sustainable Identity on Every Thing (SIoT) — a future where every physical object carries an open, web-resolvable, standards-based identity that anyone can read, verify and build upon, without proprietary lock-in. Durable, interoperable identity is the foundation of the circular economy: reuse, repair, recall, provenance, end-of-life. The tools that mint those identities should stay a public good — which is why QSeq's core is open and its identities are byte-identical across every surface.

"Sustainable Identity" is a double condition: it must be an Identity (serialized, web-resolvable, ultimately leading to a Digital Product Passport — a bare SKU is not one) and it must be Sustainable (printed true-to-size with enough error-correction margin to survive the scuffs, fading and curvature of real life). A fragile print fails the second test as surely as an SKU fails the first. QSeq exists so every code it mints passes both.

Try it

To plan a print run whose identities resolve on QDat.io, book a demo.