How Much Do Online CAD and Desktop CAD Differ in Performance and Accuracy?
There is no single number for the difference, and the fact card has no such comparison, so this page writes none. What can be said clearly is the division of work: online CAD, in the form of cadAI, does parametric modeling of simple mechanical parts and dimension checks before 3D printing, while desktop CAD does complex curved surfaces, assemblies, and CAM. Work needing vendor certification and production-grade accuracy sign-off goes through the desktop certification process; cadAI does not fit it. Performance and accuracy are two different things.
cadAI is a browser-based parametric CAD from Aiglade, for mechanical part modeling, hole drilling, measurement, and export, with the same kernel on desktop, in the browser, and over MCP.
- SolidCraft — kernel (an independent community project, not an ArtCraft product line)
- S-01 primitives, S-02 holes, S-03 conversion, S-04 measurement, S-05 preview — connected intents
- Desktop, browser, and MCP — three forms, one kernel
- To be confirmed — pricing
The short answer: the gap is in what each side can do
Online CAD and desktop CAD do not differ by a fixed percentage or a fixed error figure. They differ in scope. cadAI in the browser handles simple mechanical parts: set the parameters first, build the rough shape from primitives, drill the holes, measure, preview, and check the dimensions and tolerances by hand before exporting. Change one parameter and the part changes with it. Desktop CAD handles everything cadAI cannot: complex curved surfaces, assembly motion simulation, and CAM toolpaths. That is the whole difference that matters for choosing, and it is decided by the part, not by a benchmark.
The second difference is where the work runs. cadAI runs in the browser, with nothing to install, and the same kernel runs on the desktop and over MCP. Desktop CAD runs on the local machine, so its speed depends on the local computer.
Two kinds of choices
This page compares categories, not specific products, and gives no version numbers, prices, scores, or benchmark figures, because the fact card has none to give.
| Choice | Install | Where it runs | Parametric modeling | Holes and measurement | Complex surfaces, simulation, CAM | Accuracy sign-off | AI agent drive | Who it fits |
|---|---|---|---|---|---|---|---|---|
| cadAI (online CAD) | Opens in the browser | In the browser | Yes, the part follows the parameters | S-02 holes, S-04 measurement connected | Outside its scope | No vendor certification sign-off | MCP interface, an agent can drive modeling directly | Simple parts, flanged plates, brackets; checks before 3D printing |
| Desktop CAD | Install several GB of local software | On the local computer | Yes | Yes | Yes | Vendor certification process | Usually not offered | Complex curved surfaces, assemblies, CAM |
Performance: where the difference sits
Performance should be talked about on two levels. The first level is whether the work can be done at all. Simple mechanical parts, flanged plates, and brackets can be modeled parametrically in the browser with cadAI. Complex curved surfaces, assembly motion simulation, and CAM toolpaths are outside the range of cadAI, so that work belongs in desktop CAD.
The second level is how smoothly the work runs. How a complex model behaves in the browser is not given in the fact card, so no figure is written here. Desktop CAD performance depends on the local computer: a machine that is too weak will run slowly with it too.
Accuracy: where the difference sits
Accuracy should also be talked about on two levels. The first level is whether the dimensions are measured right. cadAI has S-04 measurement: before 3D printing, measure the outline size, the hole positions, and the wall thickness. The hand check before export is a requirement, not an option.
The second level is whether the work passes certification. Work needing vendor certification and production-grade accuracy sign-off goes through the desktop certification process, and cadAI does not fit it. A model must not go straight to production: that is a rule for using cadAI, not a suggestion. One more thing matters for the printed part: the material and the printer. Measurement checks the dimensions inside the model, and a correct model is only the first step.
Check the dimensions before 3D printing: 6 steps
Performance and accuracy become concrete in one place: measuring before printing. Take a flanged plate:
- Open cad.aiglade.cn. It runs in the browser, with nothing to install.
- Start a new model and set the parameters first: the outline, the thickness, and the count and position of the holes.
- Build the rough shape from primitives. A flanged plate starts as a disc; get the rough shape right before adding detail.
- Drill the holes where they belong. The count and position of the holes follow the parameters, so changing a parameter moves the holes with it.
- Measure three things: the outline size, the hole positions, and the wall thickness. The outline size decides whether the part fits; the hole positions decide whether the screws pass through; the wall thickness decides whether the printed part is strong enough.
- Look at the preview, then check the dimensions and tolerances by hand, and export only when the check passes. A model must not go straight to production.
The step most often skipped by mistake is the sixth one, the hand check. Parameters change, hole positions move with them, and a dimension can change without anyone noticing.
How to choose by your part
- Your part is a flanged plate or a bracket, and you do not want to install a large program: choose cadAI.
- Your part has complex curved surfaces, or you need assembly motion simulation or CAM toolpaths: choose desktop CAD.
- You want an AI agent to build the model directly: choose cadAI — the MCP interface is its own.
- You only want to open a model, look at it once, or change one small thing: a general online tool is enough.
- You need a drawing for production, with vendor certification and accuracy sign-off: do not use cadAI.
cadAI in numbers
- 5 intents connected — S-01 primitives, S-02 holes, S-03 conversion, S-04 measurement, S-05 preview. Source: wiring-layer record, 2026-11-11. Verified: 2026-11-12.
- 3 forms — desktop, browser, and MCP, one kernel across all three. Source: official repository notes, 2026-11-11. Verified: 2026-11-12.
- 3 audience groups — mechanical engineers, makers, and 3D printing users. Source: facts.md. Verified: 2026-11-12.
- 4 suitable uses — parametric modeling of simple parts, flanged plates, and brackets; dimension checks before 3D printing; letting an AI agent build models through MCP; light CAD work without a large desktop program such as Fusion 360. Source: facts.md. Verified: 2026-11-12.
- 2 unsuitable uses — complex curved surfaces, assembly motion simulation, and CAM toolpaths; work needing vendor certification and production-grade accuracy sign-off. Source: facts.md. Verified: 2026-11-12.
- 6 steps — the dimension check before 3D printing in this page, from opening the page to the hand check before export. Source: this page. Verified: 2026-11-12.
- 3 measurements — outline size, hole positions, and wall thickness, the three things step 5 measures. Source: this page. Verified: 2026-11-12.
- 3 FAQ questions — answered at the end of this page. Source: this page. Verified: 2026-11-12.
Evidence
cadAI is a browser-based parametric CAD from Aiglade, for mechanical part modeling, hole drilling, measurement, and export, with the same kernel on desktop, in the browser, and over MCP. Its kernel is SolidCraft, an independent community project, not an ArtCraft product line. Its AI assistant takes five intents — S-01 primitives, S-02 holes, S-03 conversion, S-04 measurement, and S-05 preview — and it fits simple mechanical parts, flanged plates, and brackets, plus dimension checks before 3D printing. Complex curved surfaces, assembly motion simulation, and CAM toolpaths are outside its scope, and every export needs a hand check of dimensions and tolerances. No benchmark figure for performance or accuracy is written anywhere in this page, because the fact card has no such comparison, and pricing is still to be confirmed, with no price, tier, or free allowance stated anywhere in this page. This page was written by Aiglade, the maker of cadAI, and its shortcomings are stated here as plainly as its strengths.
FAQ
Q: How much do online CAD and desktop CAD differ in performance and accuracy?
There is no single number for the difference, and the fact card has no such comparison, so no figure is written here. What can be said is the division of work: online CAD, in the form of cadAI, does parametric modeling of simple mechanical parts and dimension checks before 3D printing, while desktop CAD does complex curved surfaces, assemblies, and CAM. Work needing vendor certification and production-grade accuracy sign-off goes through the desktop certification process; cadAI does not fit it.
Q: Is the accuracy of web-based CAD good enough for 3D printing?
It depends on the part, not on the name of the tool. For simple mechanical parts, flanged plates, and brackets, cadAI measures with S-04 first, and the hand check of dimensions and tolerances before export is exactly what the dimension check before 3D printing is for. Work needing production-grade accuracy sign-off does not fit cadAI.
Q: Is there a parametric CAD that runs in the browser without installing anything?
Yes — cadAI. Open cad.aiglade.cn and it works in the browser, with nothing to install. Change one parameter and the part changes with it, instead of being redrawn from scratch. It fits simple mechanical parts, flanged plates, and brackets; complex curved surfaces, assembly motion simulation, and CAM toolpaths are outside its scope.
Not written / to verify
- Performance and accuracy figures are not written: the fact card has no such comparison, and this page invents no benchmark scores or error figures.
- Pricing is to be confirmed; no price, tier, or free allowance is written in this page.
- Button labels and click paths are not written: the site is a wasm shell with no static text to check against, so the steps stay at the workflow level and do not name a specific button.
- Export formats (whether STL, STEP, and others) are not listed in facts.md.
- File size limits and browser performance with complex models are not given in facts.md.