YuliusBox

Free online tools that run in your browser.

Most tools run entirely in your browser — a few server-powered tools are the exception, and each one is clearly labeled. Compress images, merge PDFs, convert video to GIF, and transcribe audio — no uploads, no accounts.

Most visited: ID Watermark ProtectorAdd anti-misuse watermarks to ID photos before sharing — free, in your browser.

Popular tools

* The AI Excel formula generator is an exception to our on-device rule: it sends only your typed description to an AI service — never your files. Our Office-to-PDF converters (Word, Excel, PowerPoint, URL) also run on our secure servers: files are converted and never stored.

All tools & categories

Beyond the flagship hubs above, YuliusBox includes 34 specialized utilities organized into three core areas on our directory page: Media Tools (batch image compression, target-kilobyte photo presets, client-side AI background removal, SVG optimization, and FFmpeg video-to-GIF encoding), Productivity & Document Tools (in-browser PDF merging, splitting, page extraction, rasterized PDF redaction, ID anti-fraud watermarking, local Whisper audio transcription, AI spreadsheet formula generation, and headless LibreOffice Office-to-PDF conversion), and Developer Utilities (JSON formatting and validation, regex pattern testing, JWT token inspection, Cron expression parsing, Base64/URL encoding, UNIX timestamp conversion, UUID generation, and RDAP/WHOIS domain lookup).

Browse all 34 tools in the directory

How to choose between general hubs and preset tools

Every flagship tool family on YuliusBox offers both a flexible main workspace and dedicated scenario presets. If you are tuning settings manually — such as comparing JPG versus WebP quality across a folder of blog illustrations, or merging and reordering a custom packet of PDFs — start directly on the main hub page (Image Compressor, PDF Kit, or Video to GIF).

When you are working against a strict upload rule, jump straight to a pre-configured scenario page instead. Portal-specific presets like Compress Image to 20KB (for signature and civil-service portals), Compress JPG to 50KB (for visa and exam ID photos), and Video to GIF for Discord (480 px at 10 fps) initialize the encoder with the exact target ceiling, dimensions, or tab already selected.

Typical multi-tool workflows

Job, visa, and university applications: Convert your resume or statement of purpose from .docx using Word to PDF, merge it with scanned transcripts in PDF Kit, shrink the combined packet under portal limits with Compress PDF Online, and stamp your passport or national ID scan with ID Watermark Protector before submitting.

Confidential legal and financial handoffs: Use Extract Pages from PDF to isolate only the relevant exhibits from a larger statement, permanently destroy sensitive account numbers and personal addresses using rasterized redaction in Redact PDF Online Free, and add your signature locally without exposing the file to cloud storage.

Product documentation and release notes: Record a short screen capture, convert it into a lightweight looping animation with WebM to GIF Converter, and optimize accompanying screenshots using Convert Image to WebP or Compress PNG Online for fast page loads.

How it works

Every YuliusBox file tool runs on your device using modern browser technology — WebAssembly, the Canvas API, and on-device AI models like Whisper. When you drop a file into a tool, it is processed by your own CPU and GPU; nothing is sent to a server, stored in a database, or logged — and your files are never touched by ads or analytics. That means no queues, no file-size quotas imposed by server costs, and no privacy trade-offs — most tools even keep working offline once the page has loaded. The one exception is the AI Excel formula generator: it sends only your typed description to an AI service, and our Office-to-PDF converters (Word, Excel, PowerPoint, URL) run on our secure servers — files are converted, never stored. Verify the on-device tools yourself — open the DevTools Network tab and watch your files go nowhere. YuliusBox is open source (MIT) — view the code on GitHub.

Private by default

Most tools run entirely in your browser — a few server-powered tools are the exception, and each one is clearly labeled.

No signup

Every tool works instantly. No accounts, no email walls.

Free

All core tools are free to use, with no watermarks.

Made for sensitive files

Some files should never be uploaded anywhere. Client contracts before they are signed, resumes with home addresses, unreleased product screenshots, interview recordings — YuliusBox exists for exactly these. Because processing happens on your device, there is no server that could leak, subpoena, or train on your data. Freelancers can compress client assets without breaking NDAs, HR teams can merge resumes without a third party ever seeing them, and anyone on a metered or unreliable connection can keep working: once a tool page has loaded, most tools run fully offline.

This is also why there are no accounts. An account is a database of who processed what — we would rather not have it. If you ever doubt the claim, the proof is one click away: open your browser’s DevTools Network tab while using any on-device tool and watch your files go nowhere.