Comparison
SpeakCAD vs STLsmith: two text-to-STL tools for functional parts
STLsmith and SpeakCAD aim at the same person: someone who needs a functional printed part and does not want to learn CAD. Both take a description with dimensions, apply printing rules and give you a file. STLsmith keeps it minimal: describe, refine, download an STL, with a few free tries. SpeakCAD is a fuller editor: it works as well on a phone, edits parts you upload, exports 3MF and slices G-code for your printer.Updated 23 September 2026
Sources, checked on 23 September 2026: STLsmith and its pricing · STLsmith llms.txt
| Criterion | SpeakCAD | STLsmith |
|---|---|---|
| Audience | People with a 3D printer, no CAD skills assumed | The same: functional parts without CAD |
| Where it runs | Browser on any phone, tablet or computer; nothing to install | Browser (check their site for use on a phone) |
| Inputs | Text, photos with a ruler to copy a part, STL/3MF/.scad uploads | Text, in English or Spanish |
| Editing | Chat: say what to change, the rest stays; typing a new number in the dimensions panel is free | Refine by chat (“5mm thicker”) |
| Printability | Wall thickness, clearances, flat base and overhang rules applied by default | FDM rules: 2 mm minimum walls, M3–M5 screw clearances, parts flat on the bed |
| Scope | Functional parts from hooks to multi-part enclosures; edits of uploaded STL/3MF; copies from photos | Hooks, brackets, spacers, boxes, knobs, mounts; no figurines |
| Output | STL, 3MF, OpenSCAD source, G-code sliced for your printer | STL |
| Sliced G-code | Yes, for 380+ printers: included in Pro and Unlimited, +5 credits per slice otherwise | No: open the STL in your slicer |
| Test the fit before a long print | Fit Check: free 5-minute test slice of the fit, then your printer's calibration is applied to every model | No: reprint, or cut a test piece yourself |
| Free to try | Live demo (3 AI edits of a real part, no account); 650+ ready-made library models open in a free account and resize in the viewer; your own parts and downloads use credits | 3 parts without an account, 5 more with a free account |
| Price | Starter credits $5 once (75 credits); Pro $9.99/mo; Unlimited $24.99/mo | $9 once for 100 parts; Pro $9/mo unlimited (fair use); $29 once for 500 parts with a resale licence (check their site) |
Same promise
Both tools start from the same observation: generative mesh models are wrong for parts that have to fit, and most people who need a bracket will never learn CAD. So both take a plain description with real numbers, apply FDM rules (walls, screw clearances, a flat base) and return a file that prints.
Where STLsmith wins
- Free tries of your own part. STLsmith generates three parts without an account and five more with one. SpeakCAD's free options are the live demo on a sample part and opening the 650+ ready-made library models to resize them; describing your own part uses credits.
- Price per part. $9 for 100 parts, or $9 a month for unlimited use, is cheaper per part than SpeakCAD's credits (check their site for current prices).
- A resale licence on its one-time pack.
- Simplicity. One box, one file.
Where SpeakCAD wins
- The phone. SpeakCAD's editor is built for a phone first.
- More than STL. 3MF, the OpenSCAD source, and G-code sliced with official profiles for 380+ printers.
- Starting from an existing file. Upload an STL or 3MF and change it, or copy a part from two photos and a ruler.
- Bigger parts. Enclosures with lids, multi-part layouts, threads and snap fits, with every dimension a named parameter you can change later.
- Fit Check, which calibrates clearances to your printer before a long print.
How the costs compare
STLsmith counts parts. SpeakCAD counts AI requests (2 credits each, a new part or an edit) and downloads (10 credits); small fixes after a download re-download free. A typical part with a couple of edits is about 16 credits, so Starter credits ($5 once, 75 credits) cover about 4 parts.
Verdict
Choose STLsmith for simple hooks, spacers and brackets on a computer, especially if you want to try a few parts for free. Choose SpeakCAD if you work from a phone, need 3MF or sliced G-code, want to change an existing STL, or the part is more than a simple bracket.Other comparisons
Best AI tools for 3D printing in 2026Functional parts vs figurines: the verdict first, two tables, and what is really free.SpeakCAD vs OpenSCADSpeakCAD vs TinkercadSpeakCAD vs Fusion 360SpeakCAD vs MeshySpeakCAD vs Tripo AISpeakCAD vs Shapr3DSpeakCAD vs Thingiverse CustomizerSpeakCAD vs Zoo Text-to-CADSpeakCAD vs AdamCAD (CADAM)SpeakCAD vs MakerWorld MakerLabSpeakCAD vs Backflip AI