Why the hand tools are free and the AI is not

We added five hand tools to SpeakCAD this week: Hole, Cut, Add, Round and Measure, with four starter shapes to use them on, or your own STL or 3MF. They are free. The download of a part you shaped with them is free. The AI, which was the whole product until now, still spends credits. People have asked why the line is drawn there and not somewhere more generous or more profitable, so here is the reasoning, in the open.

What a hand edit costs us

Nothing worth charging for. When you tap a face and apply a 4.5 mm hole, your phone does the work: the part is a small program, the hole is three lines added to it, and the program is compiled into a mesh by a geometry kernel running in your browser. Our servers see the saved result, a few kilobytes. We could serve a million hand edits a day on the hosting we already pay for.

Charging for that would be charging for the idea of CAD, which Tinkercad has given away for fifteen years. We are not going to win by being less free than Tinkercad at the thing Tinkercad does.

What an AI request costs us

A real amount, every time. "Add a lid with a 0.3 mm clearance and two snap hooks" sends your whole part and your sentence to a large model, which thinks for a while, writes a new version of the program, and then goes through our check loop: the result is compiled, measured against what you asked, rendered from several angles and reviewed, and if something is wrong it is sent back for a fix before you see it. On a large part that can take a minute or two of model time, and we pay for every second of it. It gets more expensive with the size of the part, which is why a request on a very large model can spend up to 10 credits instead of 2 credits.

We do not publish the per-request figure because it moves with the models we use and the size of your part. The shape of it is what matters: a hand edit is close to free for us, an AI request is not, and a price that pretends otherwise would be paid by the people who use the tools lightly to subsidise the people who send fifty requests a day. We would rather the price follow the cost.

Why the downloads of hand work are free too

Because a free tool that will not give you the file is a demo, not a tool. If you shaped a plate with four holes and rounded corners by hand, the STL is yours, at no cost, with a free account so it lands in your models. The same for the 3MF.

A download of a model that contains AI work is different: it spends 4 credits. That is where the AI's value lands in your hands, and it is where we recover what the requests cost. Small fixes after a test print re-download free, so you are never charged twice for the same part because a hole came out 0.3 mm tight. And a model you later change by hand, after paying for its AI version, follows the same small-fix rule.

The line, exactly

Shaping a part by hand (a hole, a cut, an added tab, an extruded face, rounded corners) and downloading what you shaped are free. Each AI request spends 2 credits, a download of AI work 4 credits, and G-code 5 more. G-code is included in Pro and Unlimited, because slicing with your printer's own profile is work our slicing service does for you, and those plans are priced for it.

So the free tier, with a free account and no card, is:

• The hand tools: hole, cut, add, rounded corners, measure, on the four starters (box, plate, cylinder, tray) and on any model.
• Typed numbers: every size of a starter, an AI design or a hand edit is a field you retype at no cost.
• The download, as STL or 3MF, of a part started from a starter or from your own file (handed over with nothing typed) and shaped only by hand. On a library model or a part the AI worked on, the hand edits are free and the download spends the usual 4 credits.
• The live demo, without even an account: the tools on the demo part, and 3 AI edits to see what the AI does.
• The Fit Check coupon, the small test piece that tells you how your printer's holes come out, as STL or 3MF.

And the paid part is the AI, its downloads and the G-code. There is no free trial of the AI beyond the demo; a new account shows its credit balance in the editor and the price of each request before it is sent. Plans are Maker $7.99 a month (60 credits), Pro $14.99, Unlimited $39.99, cancel anytime.

One more rule we keep because it is fair: the price of a request is shown before you send it, on the send button, and it does not change after the fact. A hand edit never changes that price, because the AI reads your hand edits as a few short lines, not as a bigger part.

Why not make the AI free too, with a cap

We tried versions of this. A free allowance large enough to finish a part gets used by people who will never pay, at our cost, and still annoys the people who would pay when it runs out mid-part. A free allowance small enough to be cheap is too small to finish anything, which makes it a worse demo than the demo. The hand tools are a better free tier than any AI allowance: they finish real parts, they do not run out, and they show you exactly where the AI is worth 2 credits, because you hit the edge of the tools yourself, with the "Ask the AI" button right there on the card.

Why not charge for the tools and give the AI away

Because the tools are the part anyone could copy and the AI is the part we are good at. The AI reads your hand edits as part of the model and keeps them; it knows what prints and what does not; it slices for 380+ printers; its results go through a check loop before you see them. That is what a credit buys. A hole where you tap should not be a business model.

What we are watching

The question we cannot answer yet is whether people who start by hand ever ask the AI anything. If they do, the free tools are the best introduction we could have built. If most parts stay by hand forever, we will have given a lot of people a free CAD on their phone, which is a fine outcome too, and we will say so here. Either way the rule above is the rule, and we would rather you read it from us than discover it at a download button.

SpeakCAD is the easiest way to design a part with real dimensions on your phone: shape it with simple tools or describe it to the AI, and download a print-ready STL, 3MF or G-code sliced for your printer.