Guide / 2026-05-20
Browser CAD is the new default for mechanical design. Not in a futurist sense, in a 2026 sense: parts get modeled, drawings get released, and G-code gets posted from a tab. The category had a long false start, then WebAssembly and WebGPU shipped, and the entire premise became real almost overnight. If you were skeptical of online CAD five years ago, you were right. If you are skeptical today, you are probably out of date.
This guide covers what browser CAD actually means, why now, what it can do, what it still cannot do, how it compares to desktop CAD and to VDI-style cloud streaming, and how to evaluate it for your team. It is written for engineers, designers, and engineering leaders making real tool decisions. We will get specific about what the underlying technology unlocks and where the edges still are.
Browser CAD is professional computer-aided design software whose workspace and renderer run inside a standard web browser. Geometry may run locally or behind a typed server API. solidSF uses a thin client: WebGPU renders derived meshes locally while the Rust kernel, sketch solver, regeneration, and export services stay protected on the server. There is no remote desktop session, Citrix client, or streamed-pixel viewport.
That distinction matters because the term "online CAD" is often used loosely. Vendors with desktop applications wrapped in a remote streaming layer like to call themselves cloud CAD or web CAD. They are not. They are a desktop app on a server with a video feed, and the user experience inherits all of the input lag, bandwidth dependency, and pixel-fuzz of any VDI workflow.
Real browser CAD has three useful properties. First, the viewport renders locally through WebGPU or WebGL instead of arriving as compressed video. Second, modeling commands and derived geometry move over compact, structured APIs. Third, collaboration and persistence use normal web transports rather than a remote desktop session. Kernel placement is an architectural choice: solidSF keeps geometry server-side so its core IP never ships to the client.
Browser CAD was not technically feasible until three platform layers all matured. Each one removed a previously hard ceiling.
WebAssembly shipped as a stable cross-browser format in 2017 and matured into a serious compile target through the early 2020s. Languages like Rust and C++ now compile to WASM with near-native performance: typically 1.0 to 1.2 times the runtime of native code for compute-heavy work. A CAD kernel can finally live in the page without being a JavaScript rewrite.
WebGPU reached cross-browser stable status in 2024 across Chrome, Edge, and Safari, with Firefox following. WebGPU exposes compute shaders, modern bind groups, and storage buffers that match Vulkan and Metal closely enough that a CAD viewport can do real GPU work: tessellation, edge silhouette extraction, ambient occlusion, picking, and GPU-accelerated booleans where appropriate. WebGL was always too limited to render dense B-rep models smoothly.
WebRTC data channels turned the browser into a peer-to-peer transport that can move CRDT operations between users at sub-50ms latency without a server round trip per keystroke. That is what makes "two engineers editing the same part" feel native instead of laggy.
Add to this stack: SharedArrayBuffer for multi-threaded WASM, OPFS (Origin Private File System) for fast on-device storage, the File System Access API for native file dialogs, and persistent BroadcastChannel for cross-tab sync. None of these existed in usable form before 2021. Together, they are the substrate browser CAD was always waiting for.
The browser CAD story has two acts. Act one is Onshape, founded in 2012 by veterans of the SolidWorks team and launched publicly in 2015. Onshape proved that parametric, assembly-level CAD could work in a browser if you accepted a thin client and ran the kernel on a server. It was the right idea executed with the platform that was available at the time. Onshape was the first product to use the phrase "cloud CAD" with technical credibility, and they earned it. They sold to PTC in 2019 for around $470 million.
For the rest of the 2010s, the category was effectively Onshape and a long tail of viewers. TinkerCAD existed for hobbyists. SketchUp had a browser edition for architectural work. Fusion 360 ran in a browser, but only as a streamed instance of the desktop application, not as native code. The technology stack would not allow anything more ambitious than that.
Act two is what we are in now. Starting around 2022, with WASM stable and WebGPU drafts working in Chrome Canary, a new generation of browser CAD started to ship. Zoo (formerly KittyCAD) opened with a text-first parametric workflow and a custom Rust kernel. OnPaste and a handful of others appeared. Shapr3D, which was originally iPad-native, expanded into the browser. solidSF, written from scratch in Rust with a custom B-rep kernel and Bryan, is part of the same wave. solidSF keeps that kernel server-side and sends only commands and derived rendering data across the client boundary.
The capability set in 2026 covers nearly everything a mid-market mechanical engineering team needs. Browser CAD is no longer a viewer or a toy.
.sldprt migration with feature-tree replay.The honest list. Browser CAD is good enough for most teams, but it is not equivalent to every desktop CAD plus simulation stack on the planet. There are real gaps.
.CATPart, Creo .prt, and NX .prt imports as editable parametric files are still limited or non-existent in browser CAD. STEP is the bridge.For a hardware startup designing a robot, a drone, a piece of industrial equipment, a consumer product, or anything in the 10 to 10,000 part range, none of these gaps matter. For an aerospace prime designing a wing, some of them still do.
The honest comparison. Desktop CAD has been the default for thirty years because it had the only stack that worked. That is no longer true.
| Dimension | Desktop CAD | Browser CAD |
|---|---|---|
| Install | Windows-only, hours, license server | Open a URL |
| Updates | Annual major version, manual | Continuous, instant |
| Hardware | Certified workstation card preferred | Any modern laptop or iPad |
| OS support | Windows only for SolidWorks/Inventor/NX | macOS, Windows, Linux, iPadOS, ChromeOS |
| Collaboration | File locking, manual share, eDrawings | Real-time co-edit |
| Pricing | $680 to $4,700+ per year | $0 to $49 per seat per month |
| Onboarding new hires | IT ticket, days | Add to team, minutes |
| Mobile review | Read-only viewer apps | Full edit on tablet |
| Large assembly simulation | Edge case: still better today | Improving fast |
| Highly specialized add-ins | Twenty years of marketplace | Growing, not matched yet |
This is the comparison most people get wrong, and it is the one that matters most. A surprising number of "cloud CAD" products are actually a desktop CAD instance running on a remote VM, with the screen piped to your browser as compressed video. The user is essentially running Citrix on a different brand. This is not browser CAD.
| Property | Cloud-streamed desktop (VDI) | Real browser CAD |
|---|---|---|
| Where the kernel runs | Desktop app in a remote VM | Client WASM or a native server service |
| Interaction model | Every input drives a remote desktop | Local UI with compact geometry commands |
| What you see | Compressed H.264 video | Native WebGPU render |
| Bandwidth dependency | High, continuous | Light, transactional |
| Offline geometry edits | Impossible | Product-dependent; solidSF requires connectivity |
| Rendering GPU | Remote GPU | Uses your local GPU |
| Looks like browser CAD | Yes (marketing) | Yes (actual) |
Ask every vendor where its kernel runs and what crosses the client boundary. A local kernel can enable offline editing; a server-side kernel can protect core geometry IP and centralize compute. Either can deliver browser CAD when the viewport renders locally and interaction is command-based rather than streamed video.
The 2026 browser CAD market, ranked by capability, with honest notes. We include solidSF because this is our blog; the comparison is otherwise straightforward.
| Product | Kernel | Browser-native | AI agents | SolidWorks migration | Entry price |
|---|---|---|---|---|---|
| solidSF | Custom Rust (server) | Thin client, local render | Bryan, 55 tools | Feature-tree replay | $29/mo |
| Onshape | Parasolid (server) | Thin client | Advisor add-on | STEP only | $1,500/yr |
| OnPaste | Custom WASM | Yes | Limited | STEP only | Free / paid tiers |
| Zoo | Custom Rust | Yes | Zookeeper | STEP only | $20-$99/mo |
| Shapr3D | Parasolid | iPad-native, browser secondary | Limited | STEP only | $25/mo |
Note: Shapr3D started as an iPad-first product and remains strongest there. Its browser version is functional but its primary interaction model is touch. We include it because users often evaluate it in the same set.
The audience is broader than the legacy CAD world admits. If any of these fits, browser CAD is the right starting point and possibly the right ending point too.
A real checklist. If you are picking a tool, walk through every item. If a vendor cannot answer any of them, you have your answer.
solidSF is browser CAD with a protected server-side Rust kernel and Bryan. Its thin client renders locally, opens SolidWorks files through server-side feature-tree replay, includes CAM and drawings, and starts at $29/mo. Students get full access free via uni.solidsf.com. The fastest way to know if browser CAD is right for your team is to open one.