Convertmaxxing
100% private

Convert anything. Upload nothing.

HEIC photos, iPhone videos, voice memos — converted right on your phone. Files never leave your device.

Toss your files in here

🔒 Everything happens on your device — nothing is uploaded, ever.

The greatest hits

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Why people stick around

🕵️ Actually private

Everything converts right in your browser. Files never touch a server — you can verify it in your network tab.

🎉 Free, no signup

No accounts, no upload limits games, no watermarks, and no sketchy downloads. Drop files, convert, download.

🎬 Images, video & audio

HEIC photos, camera RAW, iPhone videos, voice memos — one converter for all of it, built on engines professionals have trusted for decades.

How converting in the browser works

Online converters have traditionally worked one way: you upload a file, a server somewhere does the work, and you download the result. That means handing your photos, recordings, and documents to a machine you cannot see, and it is why free tiers cap file sizes — bandwidth and processing time cost the operator real money.

Convertmaxxing does the work on your own machine instead. Images run through ImageMagick — the engine that has handled this job on servers since 1990 — compiled to WebAssembly and executing inside your browser tab. Video and audio run on WebCodecs, the same hardware-accelerated pipeline your device uses to record and stream. Both are real conversion engines, not simplified imitations.

Because nothing is uploaded, there is nothing to store, scan, or lose, and no size tier to negotiate. Where the approach has genuine limits — formats we cannot create, browser encoding support that varies, memory ceilings on very large files — we say so plainly rather than shipping a broken file. The full explanation is here, including how to verify the no-upload claim yourself in about ten seconds.

Guides

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Common questions

Are my files really not uploaded anywhere?
Correct, and you can verify it rather than take our word for it. Conversion runs inside your browser using WebAssembly and your browser’s own video pipeline, so there is no upload step at all. Open your developer tools, switch to the Network tab, and run a conversion — you will see the page and the conversion engine load, and no request carrying your file.
Is there a file size limit?
There is no limit imposed by us, because there is no server paying for bandwidth or CPU time. The practical ceiling is your own device: WebAssembly memory caps out around 4 GB, so extremely large images can exhaust it. When that happens you get an honest error rather than a corrupted file.
Do I need to create an account?
No. There are no accounts, no email collection, no newsletter, and no free tier with a paywall behind it. Open the page, drop in files, download the results.
Which formats can Convertmaxxing not create?
HEIC cannot be created — no HEIC encoder is available to our engine for patent reasons, the same reason browsers do not display HEIC natively. Camera RAW formats (CR2, CR3, NEF, ARW, DNG) are read-only because RAW data can only come from a camera sensor. MOV, MKV, and ProRes are read-only too, since MP4 is the more compatible destination in every case. There is no PDF support at all.
Why did my video conversion fail when the same file worked elsewhere?
Video encoding uses your browser’s own hardware pipeline, and support varies between browsers and platforms — a combination available in Chrome may be missing in Firefox on the same machine. Rather than producing a file that will not play, the converter probes what your browser can actually encode and tells you when something is unavailable. Converting to MP3 or WAV always works, since those encoders ship with the site.
Does converting to a lossless format restore lost quality?
No. Converting a JPEG to PNG, or an MP3 to WAV, preserves exactly what is already in the file — artifacts included — in a larger container. It is genuinely useful before a round of editing, because it stops further degradation accumulating, but detail discarded by an earlier lossy save cannot be recovered by any tool.

All conversions

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