What happens when someone buys a 3D model on Ko-fi
A buyer lands on your Ko-fi shop, sees your product image, reads your description, and clicks buy. They receive a download link. They open the STL file in their slicer. And sometimes — the model doesn't match what they expected. The resolution is too low, the supports are unexpected, or the scale is wrong. Now they want a refund.
None of this is your fault. You described the model accurately. But Ko-fi gave them no way to inspect it before buying. They couldn't rotate it, measure it, or check the mesh topology. They bought blind.
The Ko-fi 3D model problem: no viewer
Ko-fi was built for general digital downloads — music, PDFs, fonts, presets. It was not built for 3D files. There is no native rendering of STL, GLB, OBJ, or 3MF. The platform cannot open these formats in a browser. When a buyer looks at your product page, they see whatever image or video you manually uploaded. If you forget to add good renders, they see nothing useful.
This creates a specific problem for 3D printing marketplaces: buyers cannot verify:
- Whether the mesh is watertight (printable without errors)
- Whether the scale matches their printer bed
- Whether the level of detail matches the listed resolution
- Whether the file contains what was advertised
For physical goods, you can request a return if the item doesn't match. For digital files, most platforms (including Ko-fi) have no return policy once a file is downloaded. Buyers know this. It makes them hesitate. Hesitation kills conversion.
What “in-browser 3D viewer” actually means for your sales
When a buyer can rotate a 3D model in the browser before purchasing, several things happen:
- Trust increases. Seeing the actual mesh — not a render — proves the file exists as described.
- Questions decrease. Buyers stop asking “what does the underside look like?” They check themselves.
- Refund requests drop. Post-purchase surprises go to near zero when buyers inspect the real mesh before buying.
- Conversion improves. Buyers who can inspect a model before buying are more likely to complete the purchase.
None of this is available on Ko-fi. The platform was not designed for it, and it has not added it.
Ko-fi's fee structure vs. keeping 100%
Ko-fi charges a 5% platform fee on every Ko-fi Shop sale (unless you pay for Ko-fi Gold, which removes it). On top of that, Stripe processing fees apply: typically 2.9% + 30 cents per transaction in most countries. A $10 model sale on Ko-fi Free leaves you with approximately $8.42 before currency conversion.
Proofly works differently. Creators keep 100% of every sale. Proofly earns only from a small buyer-side convenience fee added at checkout — it never touches your payout. A $10 model on Proofly pays you $10.
The piracy gap Ko-fi ignores
Ko-fi delivers your file. That's the end of its responsibility. If a buyer downloads your STL and shares it in a Discord server or Telegram group, Ko-fi has no mechanism to help you trace the leak. There is no buyer-specific fingerprinting, no watermark, no forensic trail.
For creators selling miniatures, game assets, or architectural models — where the community is tight-knit and files spread quickly — this is a real risk. Once your file is in the wild, there is nothing Ko-fi can do.
Proofly embeds a unique invisible watermark (HiddenMark™) into every buyer's copy at the mesh geometry level. If a file appears on a piracy forum, you upload it to the verification tool and learn the buyer's identity in under 10 seconds. The watermark survives format conversion, re-export from Blender, and most common mesh modifications.
What a Ko-fi alternative for 3D models looks like
A platform built specifically for 3D creators needs:
- Native support for STL, GLB, OBJ, 3MF, FBX, and ZIP bundles
- In-browser 3D viewer so buyers inspect the actual mesh before purchasing
- Per-buyer watermarking so leaks are traceable
- Creator keeps 100% — no percentage cut on sales
- Print settings fields (layer height, infill, supports, material) built into the upload form
- AI topology check on upload so printability issues surface before the file goes live
Proofly was built to satisfy exactly this list. It is a 3D-model-specific marketplace, not a generic digital download platform that also accepts STL files.
Moving your Ko-fi 3D shop to Proofly
You do not need to leave Ko-fi immediately. Many creators list on multiple platforms. But if you want buyers to see your models before buying — and if you want to stop losing sales to a blank thumbnail — Proofly gives you the viewer, the protection, and the full 100% payout that Ko-fi does not.
Uploading your first model takes under 5 minutes. Proofly is free to join. Your first 100 sales are covered under the Founding Creator program, which locks in your status permanently regardless of when the community grows past that threshold.
List your 3D models where buyers can actually see them
Full in-browser 3D viewer · 100% to creators · HiddenMark™ leak tracing · Free to join
Frequently asked questions
Can buyers preview 3D models on Ko-fi before buying?
No. Ko-fi displays only the images you upload to the product listing. There is no 3D viewer. Buyers see a flat photograph and purchase without inspecting the mesh.
What is a good Ko-fi alternative for selling 3D models?
Proofly is a dedicated 3D model marketplace with a full in-browser viewer for STL, GLB, OBJ, 3MF, and FBX. Creators keep 100% of every sale and every download is protected with HiddenMark™ watermarking.
Does Ko-fi support STL and GLB files natively?
Ko-fi accepts STL and GLB as digital download attachments but cannot render them in the browser. Buyers receive a raw file with no preview.
Does Ko-fi take a percentage of 3D model sales?
Ko-fi charges a 5% platform fee on Ko-fi Shop sales for free accounts, plus Stripe processing fees. Ko-fi Gold removes the platform fee but costs $8/month. On Proofly, creators keep 100% — no monthly fee, no percentage cut.
Can I protect my STL files from piracy on Ko-fi?
Ko-fi has no piracy protection for digital files. Once downloaded, files can be shared freely with no traceability. Proofly's HiddenMark™ embeds a buyer-specific fingerprint into the mesh so leaks can be traced to the exact buyer in seconds.