I built PrivateConvert because the existing options for converting a file online all required me to upload it to a stranger’s server. CloudConvert, iLovePDF, Smallpdf, Adobe’s online tools — all of them follow the same pattern: drop your file, it leaves your device, it gets processed somewhere you can’t see, and a download link comes back. Sometimes the file gets “deleted after a few hours.” Sometimes the terms quietly grant the host a license to use it for AI training. Sometimes the host gets breached and your scanned passport ends up on a hacker forum.
That whole model bothered me. A file conversion is just math. It does not need a server. It does not need an account. It does not need a privacy policy that gets quietly amended every six months. So I built one that does the math in your browser, where the file already lives, and never sends a single byte of it anywhere.
01 // What I built and why
PrivateConvert is an evolving suite of file conversion tools that all share the same architecture: the file never leaves your device. Every tool runs entirely in your browser via WebAssembly, the HTML5 Canvas API, and the FileReader API. There is no upload endpoint anywhere in the code — not disabled, not optional, not “only for premium users.” The architecture makes data leakage structurally impossible, not just against company policy.
That is the only differentiator that matters in this category. Every other “privacy-focused converter” in the SERP is a server-side tool with a privacy-flavored marketing page. PrivateConvert is the one where you can open DevTools, watch the Network tab during a conversion, and see zero outbound requests. The promise is verifiable, not stated.
If you convert a tax form, a medical scan, a passport photo, an NDA, a contract, a private chat screenshot — on a server-based converter, that file existed on someone else’s infrastructure, however briefly. On PrivateConvert, it never existed anywhere except in your browser’s memory. Close the tab and there is nothing left to forget to delete.
02 // Background
I also run HostingBuff, a long-running game-server hosting publication where I write every guide myself. That side of my work involves Linux administration, dedicated server setup, DDoS mitigation, CSP and security headers, and a lot of staring at journalctl at 2 a.m. Most of those skills translate directly to PrivateConvert: the same instinct that says “don’t expose this port” on a CS2 server is the instinct that says “don’t add a fetch call to the converter.”
The technical stack on PrivateConvert is small on purpose: static HTML, vanilla CSS, vanilla JavaScript, a couple of well-known open-source libraries (heic2any for HEIC decoding, pdf.js for PDF rendering, jsPDF for PDF generation, JSZip for batch downloads). No frameworks, no build step, no bundler, no runtime dependencies on a server I control. The whole site weighs less than a single Instagram story.
03 // Editorial principles
Five rules I hold every PrivateConvert tool and guide to:
- The file never leaves the device. Non-negotiable, architecturally enforced, audited per release.
- No cookies, no surveillance analytics. Plausible only (cookieless, EU-hosted). No Google Analytics, no Meta Pixel, no Hotjar, no Mixpanel, no exceptions.
- Honest copy. If a tool has a limitation (mobile slow for big PDFs, format X not perfectly supported), it’s stated on the page. No marketing softening.
- Verifiable claims. Every privacy promise includes “here’s how to verify it in DevTools.” Trust without verification is just hope.
- No dark patterns. No upload count limits to push paid tiers (there is no paid tier), no account walls, no “sign up for the full feature.” What you see is what you get.
04 // What I personally use
Day-to-day I use most of these tools myself, which is the only honest filter for whether a tool is worth shipping. The Image Compressor lives in a pinned tab. The HEIC converter handles every iPhone photo I send to non-Apple users. The PDF → JPG tool is how I share single pages from research papers without leaking the rest of the document.
If a tool wouldn’t pass my own “would I use this on a file I actually care about” bar, it doesn’t ship.
05 // Articles & tools I have written for this site
Every tool and accompanying explainer on PrivateConvert is written and built by me personally. The current catalog:
Image conversion tools
- HEIC to JPG Converter (Offline)
- Bulk HEIC to JPG (batch + ZIP)
- WebP to PNG Converter
- PNG to JPG Converter
- SVG to PNG Rasterizer
- PNG to ICO Favicon Generator
- Image Compressor (with before/after slider)
- Image Resizer & Cropper
Document tools
Site reference
- About PrivateConvert — the mission and architecture
- Privacy Policy — what we collect, why, and how to verify
- Contact — how to reach me
06 // How to reach me
The fastest channel is contact@privateconvert.net. I answer everything personally — bug reports, feature requests, security disclosures, press inquiries, partnership pitches. There’s no contact form because forms phone home; mailto is the most private channel available on the open web.
For media coverage about architecturally-enforced privacy or browser-based file conversion as a category, use the same email with “PRESS” in the subject line.
</end> — Keishin, founder, PrivateConvert