I built a file converter that never uploads your files — free, unlimited, and 100% local

Convertube — Tue, 13 Oct 2026 02:11:15 +0000

Think about the last file you converted online. Maybe a PDF contract you needed in Word, a batch of iPhone photos that Windows would not open, or a video you wanted as an MP3.

You almost certainly uploaded it. That is how nearly every online converter works: your file goes to someone else's server, gets converted there, and you download the result. Then you hope they really delete it.

Convertube works differently. The conversion runs entirely inside your browser, on your own device. Your file is never uploaded — not to us, not to anyone.

The four promises

1. 100% local. Every converter and every PDF tool on the site runs in your browser tab. There is no upload step and no server that could receive your file.

2. Free. No subscription, no trial, no "pro" tier, no credit card, no account. Every feature is available to everyone.

3. No limits. No daily quota, no "3 files per hour", no file-count meter, no queue, no watermark on the output. Drop in up to 20 files at a time and convert as often as you like. The only ceiling is your own device's memory — up to 2 GB per file on a desktop.

4. Nothing can leak. A file that is never sent cannot be stored, logged, analysed, sold or exposed in a breach. Contracts, payslips, bank statements, medical letters, ID scans, family photos — they stay on your machine from start to finish.

What it can do

PDF to Word, Excel, PowerPoint, JPG, PNG and text — headings, tables and pictures are rebuilt into an editable document. Start with PDF to Word.
Scanned PDFs — an AI text-recognition model reads the pages, and it runs on your device too. Make a scan searchable with OCR PDF.
14 PDF tools — merge, split, compress, rotate, crop, sign, watermark, add page numbers, add bookmarks and more.
iPhone photos — HEIC to JPG or PNG, so they open on Windows, Android and any upload form.
Video and audio — MP4 to MP3, MOV to MP4, MKV to MP4, WAV, FLAC, M4A, video to GIF and more. Container swaps such as MOV to MP4 copy the streams, so they finish in seconds with no quality lost.
Images — JPG, PNG, WebP, AVIF, GIF, TIFF, BMP, ICO and SVG, mostly converted in under a second.

80+ conversions in all, in 16 languages, on Windows, macOS, Linux, Android and iPhone. Nothing to install.

Who it is for

Anyone handling sensitive documents — HR, finance, legal, healthcare, or just your own tax return. Many companies forbid uploading internal files to unapproved cloud services; a tool that never uploads sidesteps the problem.
iPhone users on Windows — turn a folder of HEIC photos into JPGs without installing codecs or uploading your photo library.
Students and teachers — convert lecture recordings to MP3, scanned handouts to searchable PDFs, slides to images, with no account to create.
People on slow or metered connections — there is no upload or download of the file itself, so a 1 GB video does not cost you 2 GB of data.

How is this possible without a server?

Short version: modern browsers are powerful enough to run real conversion engines. When you open a page, Convertube sends the converter to your browser (as WebAssembly), and your browser does the work on your own processor. The direction is reversed: the code travels to your file, instead of your file travelling to someone's server.

That is also why it can be free and unlimited. A conversion that runs on your device costs us nothing, so there is nothing to meter and nothing to charge for. The site is paid for by ads on its pages — which see what page you are on, never what file you open.

Do not take my word for it — check in 10 seconds

Open any Convertube page and convert one file (so the converter loads).
Turn off your Wi-Fi — do not reload the page.
Convert another file. It still works, because nothing ever needed a server.

Or press F12, open the Network tab and convert something: you will see no request carrying your file. You will see other requests — Google Analytics counting the visit, and the ads mentioned above — but none of them ever contains your file. Everything the page itself sends is listed in the privacy policy.

Being honest about what it cannot do

Word, Excel and PowerPoint into PDF is not available — doing it faithfully needs a full office suite, which cannot run in a browser tab. We would rather say so than ship something broken.
Very large files are limited by your device's memory — 2 GB per file on desktop, 512 MB on phones.
Speed depends on your device. A fast laptop is quick; an old phone is slower. The first conversion of each type also downloads its engine once.
Text recognition on scans is good but not perfect — stamps, handwriting and crooked pages come out worse.

Try it at convertube.net — no sign-up, nothing uploaded, nothing to pay.

I would love to hear which conversions you use most, and what you would like added next. Feedback and feature requests are welcome in the comments.