How Dexta Studio works
All 60 tools run inside your browser tab. This page explains what that means in practice — which engine does the work, what stays on your device, and what genuinely does leave it.
Processing happens where the file already is
Most online media tools work by uploading. You hand your file to a server, it queues, something happens to it, and you download the result. That approach costs the operator real money per file, which is why those sites tend to arrive with watermarks, size caps and subscriptions — and it means a copy of your file sits on a machine you know nothing about.
Browsers no longer need that. WebAssembly runs compiled C and Rust at close to native speed, and the Canvas and WebAudio APIs give direct access to pixels and samples. So Dexta Studio ships the software to your device instead of shipping your file to ours. When you drop a file onto a tool, it is read into that tab's memory, worked on by your own CPU, and written back out as a download.
The practical consequences follow from that one decision. There is no upload wait and no queue. There is no per-file cost, so there is nothing to charge for and no reason to add a watermark. There are no accounts, because there is no server-side state to attach one to. And when you close the tab, the working copy is gone — not deleted on a schedule, simply never written down.
What does the work
The method varies by tool, because the right engine depends on the format.
FFmpeg (WebAssembly)
34 toolsDecodes, filters and re-encodes video and audio. The same FFmpeg used by desktop software, compiled to WebAssembly so it runs inside the tab.
Canvas 2D
13 toolsThe browser's own drawing surface. Images are decoded into it, transformed, and written back out — the fastest path available, with no library in between.
pdf-lib
12 toolsReads a PDF's page objects and writes new documents. Pages are copied rather than re-rendered, so text stays selectable and sharp.
pdf.js
1 toolMozilla's PDF renderer, used where a page has to become a picture — thumbnails, previews and PDF-to-image conversion.
What stays on your device
- Your video, image, PDF or audio file — it is read into the tab's memory and never sent anywhere.
- Everything you type into a tool: crop boxes, timecodes, captions, signatures.
- Every result you export, until you choose to download it.
What does leave it
Your files are not on this list, and never will be. Everything else that makes a network request is:
- The page itself, and its ads
Dexta Studio is funded by advertising, so each page loads Google AdSense. That request carries the usual web basics — your IP address, browser and referring page — the same as any ad-supported site.
- The processing engine, on first use
Video and audio tools download the FFmpeg WebAssembly build (~30 MB) from the jsDelivr CDN the first time you use one, then reuse the cached copy. That is a file coming to you, not one going out — but it does mean jsDelivr sees the request.
- An anonymous usage counter
When a tool runs we record which tool it was, whether it succeeded, and how long it took. No file data, no identifiers, no cookie. It tells us which tools to improve.
- Stock media searches, only if you use them
The video editor can search free stock libraries. If you search one, your search term goes to our worker so it can query the provider. Your own files are never part of that request.
The honest trade-offs
Working in the browser is not free of cost — it moves the cost to your device. Your file has to fit in the tab's memory, so the practical ceiling is your hardware rather than a number we set: a recent laptop handles far more than an older phone, and a very large video can exhaust either. There is no hard cap in the app, which also means no warning before you reach yours.
Encoding speed is your CPU's speed. A long video takes minutes rather than seconds, and it uses a single thread — the multi-threaded FFmpeg build requires a security header that would break other parts of the page, so we use the single-thread one. A few operations, reversing in particular, need the whole clip in memory at once and are genuinely limited to short files.
And some things simply are not possible in a browser: HEIC and camera RAW cannot be reliably decoded, so those formats are not supported. Where a limit like that applies to a specific tool, it is written on that tool's own page rather than buried here.