Rayon Raises €10 Million to Rebuild Interior Design Software Around the Browser and AI

Rayon, a Paris-based startup that builds browser-based drawing software for interior designers, has raised €10 million in a Series A round led by Partech. Existing investors Northzone, Foundamental and Seedcamp also participated, bringing total funding to nearly €16 million.

The round, announced on 29 September 2026, will help Rayon expand its artificial intelligence capabilities and add 3D features, as it seeks to replace the desktop software that has dominated professional design for decades.

Founded in 2021 by Bastien Dolla and Stanislas Chaillou, Rayon lets design teams import PDFs, images and DWG files, edit floor plans together in real time, keep specifications alongside drawings and share projects through links rather than exchanging static files. Its customers include Virgin Atlantic, which uses the software to design airport lounges.

Why design software is ripe for change

Professional design software has long been built for desktop computers. Tools for computer-aided design, or CAD, are powerful but complex, with steep learning curves, expensive licences and file formats that make collaboration difficult. Designers often exchange files by email or shared drives, working on separate copies and reconciling changes manually.

That model has already been disrupted in other fields. Google Docs and Sheets changed how people write and analyse data by moving work into the browser and allowing real-time collaboration. Figma did the same for user interface design, overtaking established desktop tools and becoming one of the most valuable software companies of its generation. GitHub transformed software development by making code collaboration seamless.

Rayon is betting that the same shift can happen in architectural and interior design. By running entirely in the browser, it removes the need for installations and powerful hardware, and allows designers, clients and contractors to work on the same plan at once. Specifications, such as materials, furniture and finishes, can be attached directly to drawings rather than managed in separate spreadsheets.

AI in the design workflow

Rayon is also integrating artificial intelligence directly into the design process. The company already offers a floor-plan vectoriser that converts scanned or photographed plans into editable drawings, a task that designers often perform manually when working with existing buildings. It also offers a tool that generates design blocks, reusable elements such as furniture and fixtures, from images.

A new version of the software, expected later this year, will add further AI and 3D capabilities. The investment thesis, however, is less about generative AI producing designs from scratch and more about removing friction from existing workflows. For designers, the value lies in spending less time on repetitive tasks, such as redrawing plans or updating specifications, and more time on creative decisions.

Measurable returns

Rayon has emphasised measurable workflow savings in its pitch. The company says customers CityHub and Coloc Housing report monthly savings of roughly €10,000 and €11,000 respectively from using its software. Those figures are supplied by customers and the company, but they suggest that Rayon is selling on the basis of economic value rather than novelty.

For businesses that manage many properties, such as hospitality groups, co-living operators, retailers and corporate real estate teams, design is a recurring activity rather than a one-off project. Every new location, renovation or refurbishment requires plans, specifications and coordination with suppliers. Software that speeds up that process and reduces errors can deliver significant savings over time.

The Virgin Atlantic example illustrates the appeal for large brands. Airport lounges are high-profile spaces that must reflect a consistent brand identity across locations while adapting to different building constraints. Collaborative, browser-based design tools make it easier for central brand teams and local partners to work together.

A competitive landscape

Rayon competes with established design software providers, most notably Autodesk, whose AutoCAD and Revit products are industry standards, as well as a range of tools aimed at interior designers and architects. Incumbents have been adding cloud and collaboration features to their products, and some newer startups are also targeting browser-based design.

To win, Rayon must convince designers that its tools are powerful enough for professional work while being easier to use and more collaborative than the alternatives. It must also handle compatibility with existing file formats, since design projects involve many parties using different software. The ability to import DWG files, the standard format for CAD drawings, is critical in that respect.
## The founders' vision

Co-founder Stanislas Chaillou, trained as an architect, has written and spoken widely on the application of artificial intelligence to architecture. Together with Bastien Dolla, he has built Rayon around a simple premise: designers deserve tools as intuitive and collaborative as those now common in other professions, and they should not need weeks of training to become productive.

That premise shapes the product's design. Rayon aims to make common tasks, such as laying out a room, placing furniture, annotating materials or preparing a client presentation, achievable in minutes rather than hours. For smaller studios without dedicated CAD specialists, that accessibility can be as important as any advanced feature.

That vision extends beyond individual productivity. By keeping drawings, specifications and comments in a single shared environment, Rayon aims to become the system of record for a design project, the place where decisions are made and tracked. If it achieves that position, it could expand into adjacent areas such as procurement, cost estimation and project management, creating a broader platform for the businesses that design and fit out physical spaces.

Europe's design software moment

Rayon's raise is part of a broader wave of European startups building vertical software for specific professions, often with AI embedded in the workflow. Investors such as Partech and Northzone have backed several companies aiming to modernise tools for architecture, engineering and construction, sectors that have historically been slower to digitise than finance or media.

The opportunity is significant. The global construction and real estate industries are enormous, and design is a critical early step that shapes costs, timelines and quality. Better tools can reduce errors that are expensive to fix later in construction, improve communication between designers and clients, and help firms meet growing demands for sustainable, efficient buildings.

For designers in fast-growing markets such as India, where commercial real estate, hospitality and residential interiors are expanding rapidly, browser-based tools could also lower the barrier to professional-grade software. If Rayon can prove that its approach works at scale, it could help redefine how spaces are designed, from Paris and London to cities around the world.