OnyxPDF Review: 50 Free Tools That Never See Your Files
Quick answer: OnyxPDF is a free, no-signup collection of 50 PDF and image tools that run entirely in your browser — merge, compress, OCR, redact, plus an AI background remover that processes your photo on your own device. We tested the background remover anonymously: 22 seconds, transparent PNG out, "your photo was never uploaded." No account, no watermarks, no daily limits.
| Verdict | 9/10 — the rare free-tool site whose privacy claim is architectural, not a promise |
|---|---|
| No sign up? | Yes — no account exists to create; it's a static site with no backend |
| Price | Free — all 50 tools, no counters, no paywalled features found |
| Best for | Background removal and PDF tasks on files you'd rather not upload anywhere |
| Watch out for | First-use AI model download (~100 MB); speed depends on your device |
What is OnyxPDF?
OnyxPDF (onyxailabs.github.io/onyxpdf/) is a collection of 50 free tools — 32 for PDFs, 18 for images — built as a static site with no server behind it. Merge PDFs, compress one to an exact KB for a form upload, run OCR in seven languages, redact truly (re-rendered so hidden text can't be copied back), sign, watermark, convert HEIC, make passport photos, generate favicons. Every tool runs as JavaScript on your device: open your browser's Network tab while using it and you'll see nothing leaving. It works offline once loaded.
The AI credential is the Background Remover, tagged "AI · NEW" on the site: it downloads an IS-Net segmentation model into your browser and removes photo backgrounds locally, outputting a transparent PNG. That puts it in our no-signup image tools category on the strength of a genuinely on-device model — not a free trial of a cloud API.
The no-signup test
Clean browser, no account — and here there isn't even an account system to join. I opened the Background Remover, uploaded a 400×400 test image, and clicked "Remove Background." The page downloaded the AI model plus runtime (~102 MB, first use only, cached afterwards) and reported: "Done in 22s — background removed on your device. Your photo was never uploaded." The download button produced a 400×400 transparent PNG. Total first-run cost: about 90 seconds of model download; subsequent runs skip it.
No login, no email, no payment prompt appeared anywhere in the flow — or anywhere on the site. The homepage's pitch line is unusually honest for the category: "no sign-up, no watermarks, no daily limits." Smallpdf stops free users at 2 tasks a day; Sejda at 3 per hour. Here there is no counter at all. The only ads are third-party iframes that don't touch the tools.
Private by architecture, not by promise
This is the point worth lingering on. Most "private" tools ask you to trust their privacy policy; OnyxPDF asks you to trust your browser's Network tab instead. There is no upload server — the architecture makes exfiltration impossible rather than merely prohibited. For sensitive documents (contracts to redact, IDs for passport photos, medical scans to OCR), that difference matters. It's the same reason our privacy-leaning picks earn their place: the guarantee is structural.
Free limits: what's actually free
Everything we could find — all 50 tools, no daily caps, no watermarked outputs, no "pro" tier dangling. The real costs are infrastructural and honest: the AI model downloads once (~100 MB), and processing speed depends on your device rather than a server farm. An old phone will feel the 22-second background removal more than a desktop. That's the trade for files that never leave your hands.
Best for
- Background removal without uploading: product photos, profile pictures, memes — the photo stays on your device
- Everyday PDF chores: merge, split, compress, sign, and redact without creating yet another account
- Sensitive documents: redact, OCR, or convert files you'd rather not send to a stranger's server
- Offline work: once loaded, the tools keep working with the internet off
Limitations
- First-use download: the AI model plus runtime is ~100 MB before the first background removal
- Device-dependent speed: no server farm — a slow device means slow processing
- Model quality ceiling: on-device IS-Net is good, not magic; wispy hair and complex edges vary
- Browser-only: no mobile app; it's a website that happens to work offline
OnyxPDF vs the alternatives
Against iLovePDF/Smallpdf: they process your files on their servers and meter free users to a few tasks a day; OnyxPDF processes locally with no meter. For quick, private jobs, it's not close.
Against remove.bg and its clones: they run bigger cloud models and handle tricky edges better, but your photo goes to their servers and free tiers are capped. OnyxPDF's on-device model is the pick when the photo shouldn't travel.
Against a full AI image generator: different jobs — generators create images, OnyxPDF edits the ones you have. They complement rather than compete.
FAQ
Is OnyxPDF really free with no sign up?
Yes. We opened the site and ran the AI background remover end to end in a clean browser — no account, no email, no payment prompt at any point. The homepage states plainly: no sign-up, no watermarks, no daily limits.
How does the AI background remover work without uploading my photo?
On first use it downloads an IS-Net AI model (about 91 MB, plus runtime) into your browser and caches it. After that, the photo is processed locally on your device — the page told us "Your photo was never uploaded." Our test image came back as a transparent PNG in 22 seconds.
What are the 50 tools?
32 PDF tools — merge, split, compress, OCR, redact, sign, watermark, convert to Word/Excel — and 18 image tools — compress to an exact KB, resize, HEIC conversion, passport photos, meme maker, favicon generator, and the AI background remover. All run as JavaScript in your browser.
Does it work offline?
Once loaded, yes — there is no upload server, so the tools keep working with the internet off. The AI model downloads once and is cached for later use.
What's the catch compared to iLovePDF or Smallpdf?
The big sites cap free users at 2–3 tasks a day and process your files on their servers. OnyxPDF has no counter at all — the only limit is your device's memory — and your files never leave your computer. The trade is a first-use AI model download and processing speed that depends on your device.
Verdict
OnyxPDF is what free tools look like when there's nothing to upsell: fifty of them, no accounts, no counters, no watermarks — and a privacy story you can verify in the Network tab instead of taking on faith. The on-device AI background remover is the headline, but the whole suite earns its place.
9/10. The best no-signup utility suite we have tested. For background removal on photos that shouldn't leave your device, start here before reaching for a cloud service.
Tested 2026-10-24 · Providers change their signup policies — we re-verify regularly.