File converter FAQ: safe, free, private, and how it actually works

The short version: what hushvert is and is not

hushvert is a file converter built around one structural promise: for everything a browser can do, your file never leaves your device. Image conversions, HEIC decoding, audio, archives (ZIP, TAR, TGZ), PDF page operations like merging and rasterizing, and small video re-encoding all run client-side using WebAssembly. There is no server holding those files, because there is no upload to begin with.

This matters because the usual privacy copy on converter sites ("your files are safe", "deleted automatically") is not something you can check from the outside. A server-based converter has to send your file to a machine you do not control, so you are trusting a policy. In March 2025 an FBI field office publicly warned that some free online file-converter sites are used to push malware and scrape uploaded files for sensitive data, which is exactly why "trust us" is not good enough for a tax form, a medical scan, or a private photo. hushvert answers that structurally rather than with reassurance: the work happens in your tab, and you can prove it.

We are also honest about the exception. A few conversions genuinely cannot run in a browser, so they use a clearly labeled server lane. We tell you which lane a conversion uses before you start, and we never hide an upload behind friendly words.

How to read this FAQ

The questions below are grouped loosely by what people actually ask: safety and privacy first (is it safe, does it upload my files, how do I verify, are files deleted), then the practical stuff (is it free, do I need an account, size limits, credits), then the technical details (open source, offline, EXIF/GPS, formats, lossy vs lossless).

Where a claim is something you can verify or want a deeper guide on, the answer links straight to the proof. The single most useful page is /privacy-proof, which runs a live airplane-mode demo and counts the network requests during a conversion so you can watch that nothing leaves your browser. If you want a tool-agnostic method that works on any converter (not just this one), see the guide on how to verify a converter does not upload. If you only read one answer, read the first three.

Keep reading

• How to verify a converter does not upload your file
• See the no-upload proof
• Private file converter
• How hushvert keeps your files private
• The open-source engine and developer API

Common questions

Is hushvert safe to use?

Yes, and the design lets you confirm it rather than just trust it. For every conversion a browser can run (images, HEIC, audio, archives, PDF page operations, small video), your file is converted on your device and is never uploaded, so there is nothing to leak, breach, or retain. You can prove this with the airplane-mode test or the browser Network tab. The conversion engine is also open source under the MIT license, so you can read exactly what runs in your tab. For the conversions that do use a server, the lane is clearly labeled and the files are deleted quickly. See /are-online-file-converters-safe for the full safety breakdown.

Does hushvert upload my files?

For everything a browser can do, no. Image, HEIC, audio, archive, PDF page, and small-video conversions all run client-side, so the file never leaves your browser. The only conversions that upload are ones a browser physically cannot run: office documents to PDF, PDF to Word, and large video. Those use a clearly labeled server lane, and the dropzone tells you before you start. You can watch the no-upload behavior live on /privacy-proof.

Is hushvert free?

Every in-browser conversion is unlimited and free, forever, with no account. That covers images, HEIC, audio, archives, and PDF page operations. The server lane (office docs to PDF, PDF to Word, large video) is free for 2 conversions per day anonymously, then 5 per day plus 150MB per day with a free email account. Beyond that you can buy a one-time $5 Week Pass or credits that never expire. There is no subscription. Full numbers are on /pricing.

Do I need an account to convert files?

No, not for browser conversions. Image, HEIC, audio, archive, and PDF page conversions need no account, no sign-up, and set no cookies: drop a file, convert, download. You only create a free email account if you want to do more than 2 server-lane conversions per day (office docs to PDF, PDF to Word, large video), which raises your free limit to 5 per day plus 150MB per day.

How do I verify that nothing is uploaded?

Two ways, both quick. The airplane-mode test: load the page fully, turn on airplane mode or disconnect your network, then convert. If it still works offline, your file was never uploaded, because there was nowhere to send it. The Network-tab test: open your browser's developer tools, go to the Network tab, and watch for any outbound request the size of your file during a conversion. On a browser conversion you will see none. We host a live version of the airplane-mode test on /privacy-proof, and there is a step-by-step guide at /how-to-verify-converter-no-upload that works on any converter.

Which conversions stay on my device, and which use a server?

On your device (client-side, no upload): image conversions among JPG, PNG, WebP, AVIF, BMP, TIFF, SVG, JXL, and ICO; HEIC decoding to JPG, PNG, WebP, or AVIF; audio across MP3, WAV, FLAC, OGG, M4A, AAC, AIFF, and WMA, plus extracting audio from video; archives (ZIP, TAR, TGZ); PDF page operations (merge PDFs, PDF to JPG or PNG, PDF to text, and images or text to PDF); and small video re-encoding. On a server (clearly labeled, upload required): office documents to PDF (DOCX, DOC, XLS, PPT, PPTX, XLSX, ODT, ODS, ODP, RTF, HTML), PDF to Word, and large video. HEIC is never sent to a server.

Are my files deleted, and when?

For browser conversions there is nothing to delete, because the file was never uploaded; it stays on your device the whole time. For the server lane, your input file is deleted immediately after the conversion completes, and the output file is deleted within about an hour. The storage layer also enforces this automatically, so files do not linger even if something goes wrong. See /how-hushvert-privacy-works for the details.

What is the file size limit?

In-browser conversions are limited mainly by your own device's memory rather than a hard cap, since the work runs locally. For the server lane, free usage allows up to 150MB per day with a free email account, and paid usage supports files up to 2GB. The exact figures and lane-by-lane limits are published on /pricing.

Is there a subscription?

No. There is no recurring subscription anywhere. The paid options are one-time only: a $5 Week Pass, or credits that never expire. Browser conversions stay unlimited and free regardless. See /pricing for the full breakdown.

Do credits expire?

No. Credits never expire. Once you buy them they stay on your account until you use them, with no monthly reset and no recurring charge. The Week Pass is the time-boxed option (one $5 charge, no renewal); credits are the permanent one. Details are on /pricing.

Is hushvert open source?

The conversion engine is open source under the MIT license, published as @hushvert/engine on npm and GitHub. That means the actual code that runs in your browser and converts your files is public and auditable: you can read it, run it, and confirm it does what we say. Developers can also embed it directly; see /for-developers.

Does hushvert work offline?

In-browser conversions do, once the page and its codec have loaded. That is exactly the airplane-mode test: load the converter while online (this downloads the page and the conversion engine once), then turn off your network and convert. If it works offline, the conversion is running entirely on your device. The server-lane conversions (office docs to PDF, PDF to Word, large video) need a connection, because the upload is the whole point of that lane.

Does hushvert strip EXIF or GPS metadata from my photos?

Because image conversions run on your device, your photo and its metadata are never sent anywhere to begin with, which is the bigger privacy win. Whether specific EXIF or GPS fields carry over depends on the formats involved: converting to a format that does not support a metadata field will drop it. The key point is that nothing about your photo, metadata included, is uploaded during a browser conversion. For iPhone photos specifically, see /convert-iphone-photos-without-uploading.

What formats are supported?

Images: JPG, PNG, WebP, AVIF, BMP, TIFF, SVG, JXL, ICO, and HEIC decoding. Audio: MP3, WAV, FLAC, OGG, M4A, AAC, AIFF, WMA, plus extracting audio from MP4, MOV, MKV, WebM, and AVI. Archives: ZIP, TAR, TGZ. PDF: merge PDFs, PDF to JPG or PNG, PDF to text, and images or text to PDF. Video: small re-encoding in the browser, large video on the server. Documents (server lane): DOCX, DOC, XLS, PPT, PPTX, XLSX, ODT, ODS, ODP, RTF, and HTML to PDF, plus PDF to Word. The home page lists every available pair.

Why are HEIC conversions never done on a server?

HEIC decoding stays client-side on purpose, for patent reasons tied to the HEVC codec. The upside for you is that every HEIC conversion (HEIC to JPG, PNG, WebP, or AVIF) runs entirely in your browser and is never uploaded, no matter what. If you want to understand the format, see /what-is-heic, view HEIC files with /heic-viewer, or convert with /convert-heic-to-jpg-without-uploading.

Does hushvert use cookies or track me?

No cookies. We use privacy-respecting analytics only, which records aggregate usage without identifying you, and your files are never part of it. For browser conversions, the file content never leaves your device, so there is nothing for analytics to see even in principle. The Network-tab test makes this visible: the only outbound traffic during a browser conversion is, at most, a tiny analytics ping (well under the size of any real file), never your file.

Is it actually private, or just marketed as private?

It is private by architecture, and that is the difference. A server-based converter can promise privacy but still has to receive your file; you are trusting a policy. hushvert's browser conversions never send the file at all, which is something you verify, not believe. A CI test runs on every code change and fails the build if any file byte leaves the browser during a client conversion, so the no-upload guarantee cannot quietly regress. Run the live test on /privacy-proof or read /private-file-converter.

What happens when I hit the free server-lane limit?

You will see a clear gate, not a silent failure. Anonymous users get 2 server conversions per day; once you reach that, creating a free email account raises you to 5 per day plus 150MB per day. If you need more than that, you can buy a one-time $5 Week Pass or non-expiring credits. Your file is held while you decide and the conversion resumes after you continue, so you do not lose your place. Browser conversions are never gated. See /pricing.

Will converting to JPG or MP3 lose quality?

It can, because those are lossy formats. Converting to a lossy target (JPG, MP3, OGG, AAC, M4A, or WebP and AVIF at lossy settings) re-encodes and discards some data. Converting PNG to JPG also drops transparency. Lossless-to-lossless conversions preserve data exactly: WAV to FLAC, or PNG to TIFF, for example. Lossless image formats are PNG, TIFF, and BMP; lossless audio formats are WAV and FLAC. hushvert does no hidden extra server re-compression on browser conversions.

Can I convert files on a Mac or Windows without uploading?

Yes, that is the default for any browser conversion, on any operating system, because the work happens locally in your browser. We have platform-specific walkthroughs at /convert-files-on-mac-without-uploading and /convert-files-on-windows-without-uploading. For trusted offline alternatives you may already have, macOS Preview handles many image exports, ffmpeg handles audio and video, Audacity handles audio, and 7-Zip handles archives.

Can developers use the conversion engine in their own apps?

Yes. The engine is published as @hushvert/engine under the MIT license, so you can install it from npm and run the same client-side conversions inside your own application, with the same no-upload behavior. See /for-developers for how to integrate it.

Why should I trust a converter I have never heard of?

You should not have to, and the whole product is designed around that. Instead of asking for trust, hushvert gives you three things you can check yourself: a live airplane-mode demo on /privacy-proof that counts network requests during a conversion, a CI test that fails the build if any file byte leaves the browser, and an open-source MIT-licensed engine you can read line by line. Verification beats reputation. The guide at /how-to-verify-converter-no-upload shows you how to run the same checks on any converter.