Free online tools, in your browser.
Nothing ever uploaded.
245 free tools that run inside your own browser — PDF, image, video, audio, text, developer utilities and calculators. Your files never reach a server: the work happens on your device.
- Your files never leave your device
- No sign-up, no watermarks
- Most tools work offline after first use
Browse by category
Every one of them runs on your device. Pick a category, or search above.
Good places to start
Hand-picked tools to get you started.
Change a file's format
41 conversions across five categories, or drop any file into the universal converter and it will work out the options.
No upload. No server. No copy.
Most converters ask you to hand your file over first. This one never receives it.
Everything runs locally
Modern browsers can run real conversion engines — including ffmpeg — through WebAssembly. Your own CPU does the work, not a server somewhere.
Nothing is uploaded
Files are read straight from your disk into browser memory. There is no upload step, no storage, and no copy of your file anywhere but your device.
Saved straight back
The result is assembled in memory and handed back to you — single files directly, batches bundled as a ZIP.
Questions, answered
Are my files uploaded to a server?
No. Every conversion runs entirely in your browser using WebAssembly and native browser APIs. Your files never leave your device — we could not see them even if we wanted to.
Is it really free? What's the catch?
Yes, free — no accounts, no daily quotas, no watermarks and no paid tier. The work itself happens on your device, so there are no server costs to pass on to you.
Is there a file size limit?
There is no limit we impose, and no quota tied to an account — but because the work happens in your browser rather than on a server, your browser sets a technical ceiling. The media engine can address at most 2 GB of memory, and that has to hold the input, the output and the encoder at once, so audio and video files above roughly 900 MB cannot complete. The site checks the size and tells you before you start rather than failing partway through. Images, PDFs and data files are far lighter and rarely come close to any limit.
Which formats are supported?
Images: PNG, JPG, WebP, BMP, GIF and ICO. Video in: MP4, MOV, MKV, AVI, WebM, M4V, MPG, 3GP, FLV and WMV; out: MP4, WebM, GIF, or the audio track on its own. Audio: MP3, WAV, M4A, FLAC, OGG, AAC, WMA, Opus, AIFF and AMR. PDF to and from images. Data files: CSV, JSON, YAML, Markdown, HTML, TXT and Base64. One thing worth noting: a GIF you upload is read as a still image (its first frame), while GIF as an output is a real animation made from video.
Why is the first video conversion slow to start?
The media engine (ffmpeg compiled to WebAssembly, about 32 MB) is downloaded once on first use and then cached by your browser. Later conversions skip that download. Speed depends on your device — nothing is uploaded, so there is no upload wait at all.
Do you use cookies or see my files?
Your files are never uploaded, so we cannot see them. The site sets no cookies and loads no advertising or analytics scripts — see our privacy and cookies page for details.
Does it work offline?
Mostly, yes. After your first visit the site installs a small service worker. It keeps a copy of each page you open and of the engines served from this site, plus the audio and video engine once you have used it, so those tools keep working with no connection. The OCR and AI tools (background removal, face blur, transcription, automatic subtitles, translation, text-to-speech and AI upscaling) load parts of their engines from public CDNs that the service worker does not store, so they may need a connection again. The very first load of any page or engine always needs the network.