GatesFlow vs. Autodesk Viewer vs. eDrawings vs. Onshape Free: Which Free CAD Tool Actually Works for Manufacturers?

If you make parts for a living and you're comparing free CAD tools, here's the pattern you'll find: every one of them is genuinely useful — right up to a wall. The wall is different for each category, but it's always there, and it's usually in the fine print.

We build one of these tools, so read this as an opinionated comparison — but every claim about the others is checkable, and we've linked the walls so you can verify them. Everything below is accurate as of mid-2026; licensing terms change, so check before you commit.

The quick answer

Free viewers: Autodesk Viewer, eDrawings

What they're good at. Autodesk Viewer opens 80+ formats in the browser with measure and markup — for a one-off "what does this part look like," it's genuinely good. eDrawings is SolidWorks' free viewer with solid measurement tools, though it's a desktop install, which matters on locked-down shop computers.

The wall. They're file viewers, not part viewers. There's no concept of a current revision, no part record, no history. You view a snapshot, the review ends, and everything anyone learned goes back into email. The moment engineering revs the part, every copy that was ever shared is silently wrong — the exact problem we described in how to share CAD files securely.

Looking for an eDrawings alternative?

If you like eDrawings but need something that runs in the browser — no install, no IT ticket, works on a locked-down shop computer or a tablet — GatesFlow's free online CAD viewer covers the same viewing and measuring jobs, adds link-based sharing with revision control, and stays free for commercial use.

Looking for an Autodesk Viewer alternative?

Autodesk Viewer is excellent at showing you a file once. If your files are parts — with revisions, suppliers, and quality requirements attached — the alternative isn't a better viewer, it's a viewer connected to a part record. That's the difference GatesFlow is built around: same browser viewing, plus one current revision, an audit trail, and a path into document control and production.

Free CAD tiers: Onshape Free, Fusion 360 personal

What they're good at. These are real CAD systems — you can model parts, not just view them. Onshape runs fully in the browser with excellent version control.

The wall — read the license. Onshape's free plan makes every document public and prohibits commercial use, and its terms grant other users a license to use and adapt what's in your public documents. For a manufacturer holding customer NDAs or ITAR data, that's not a limitation — it's a disqualification. Fusion 360's personal license is non-commercial (hobbyist thresholds), capped at 10 active documents, and strips out the collaboration, data management, and SolidWorks/CATIA translators. FreeCAD is truly free and open source, but it's a desktop install with no built-in collaboration at all.

These are fine tools for hobbyists. They are not free tools for businesses — that's precisely the use they're priced to exclude.

Design-review platforms: CoLab, CAD ROOMS

What they're good at. Purpose-built CAD review: share links, threaded feedback on geometry, audit trails. Functionally the closest thing to GatesFlow's viewer.

The wall. Two of them. First, there's no meaningful free tier — CoLab is sales-quoted enterprise software. Second, they end at review: the model never becomes a BOM, a control plan, or a work order. You'll still buy and integrate separate systems for documents, quality, and production — and re-enter the same part data into each one.

And one cautionary tale: GrabCAD Workbench

GrabCAD Workbench was the free CAD collaboration tool for years — until it was discontinued and user data was deleted on its 2023 shutdown. Free tools that exist as an orphaned side project eventually get turned off. GatesFlow's free tier isn't a side project — it's the front door to our platform, which is exactly why it stays free: every person who opens a shared model is a reason for the next plant to join. We've written before about what vendor lock-in and shutdowns cost manufacturers.

The actual difference: what happens after viewing

Here's the test that separates GatesFlow from everything above: what can the model become?

In a viewer, the model becomes a screenshot in an email. In Onshape Free, it becomes public property you can't use commercially. In CoLab, it becomes a resolved review thread.

In GatesFlow, the same model keeps going: it gets document control with one current revision and an audit trail; its assembly structure becomes a BOM; the BOM feeds FMEAs, control plans, and PPAP packages; and those feed work orders, scheduling, and inventory — one system from "customer sent a STEP file" to "parts shipped." A measurement made during design review can become an inspection characteristic on the floor without anyone re-typing it.

And the entry point is genuinely free: commercial use allowed, designs private by default, no per-viewer charges for the suppliers and customers you share with.

Bottom line

• Need to glance at one file, once? Autodesk Viewer is fine.
• Hobby projects with no commercial angle? Onshape Free or Fusion personal.
• Enterprise design review with budget to match? CoLab will demo it for you.
• Making real parts, commercially, and tired of re-entering the same data into disconnected tools? Create a free GatesFlow account — start with the CAD viewer, and let the model keep going.