Tools that keep your files yours

Free browser tools that never upload your files

Everything happens inside your browser: open the page, drop a file, get to work. Nothing travels to a server, nothing to sign up for, nothing to pay.

Zero uploads No account No watermarks Works offline

Every tool

Each tool gets its own page, its own explanation, and works just as well on a phone as on a laptop.

PDF ToolsMerge, split, compress, rotate, number and convert PDFs with zero uploads.Open tool Compress imagesConvert and compress JPG, PNG, HEIC and TIFF to WebP, AVIF or JPG with zero uploads.Open tool CSV to SQL and moreTurn CSV, JSON, XML or Excel into SQL INSERTs, JSON, YAML, Markdown and more, with zero uploads.Open tool Time zone meeting plannerFind the best hour for a meeting across countries, with daylight saving warnings.Open tool Email signature generatorBuild a professional signature that actually renders in Outlook, Gmail and Apple Mail.Open tool Barcode label generatorGenerate labels in bulk and lay out the sticker sheet as a PDF that prints in register.Open tool JSON formatter and validatorFormat, validate and explore JSON in a tree view, and convert it to YAML or JSON Lines.Open tool Word and character counterCount words and characters live, with reading time, keyword density and readability.Open tool Secure password generatorPasswords and passphrases from the browser's cryptographic generator, with the real entropy shown.Open tool QR code generatorBuild wifi, contact, link or event QR codes, read them from an image, and generate batches from a CSV.Open tool
Unit converterConvert length, weight, temperature and nine more categories, with the formula shown.Open tool

Inside:LengthWeightTemperatureAreaVolumeSpeedTimePressureEnergyPowerAngleData storage

Base64 encoder and decoderText and files to Base64 and back, with UTF-8 done right and the data URL ready to paste.Open tool Compare two textsSee the differences between two versions line by line and word by word, with a patch ready to download.Open tool Case converterTwelve text and code formats, plus cleanup for messy pastes and URL slugs.Open tool Hash and checksum generatorMD5, SHA-1, SHA-256, SHA-384 and SHA-512 of a text or of a huge file, without uploading it.Open tool Regex testerTest and understand your expression: live highlighting, piece-by-piece explanation and replace.Open tool Unix timestamp converterTimestamp to date and back, in your zone, UTC and one you pick, with automatic unit detection.Open tool Markdown editor and HTML converterWrite Markdown and see it live. Get clean HTML, inline-styled HTML for email, or convert the other way round.Open tool URL encoder and UTM link builderEncode and decode URLs, break one apart with editable parameters, and build campaign links with their QR code.Open tool SQL formatterIndent and highlight your queries across five engines. Handles CTEs, window functions and whole stored procedures. Minifies and parameterises.Open tool Favicon generatorThe whole pack from your logo: the multi-size .ico, the PNGs, the manifest and the tags ready to paste.Open tool Crop imageDraggable frame with a thirds grid and the exact size for every social network. Rotate, flip, pad to square and crop in batches.Open tool
Colour toolsWheel picker and converter between HEX, RGB, HSL, HSV and CMYK, palette generator, contrast checker and extractor from a photo.Open tool

Inside:PickerPalettesContrastExtract

Gantt chart makerSchedule with draggable bars, critical path, non-working days and PNG, SVG, PDF and CSV output. No sign-up.Open tool

Guides

Specific problems, solved end to end.

How to merge PDFs without uploading them anywhereIs it safe to merge PDFs online? How to combine contracts, IDs or payslips without uploading them, what Mac and Windows offer, and how to verify it yourself.Read the guide Reduce image file size without visible quality lossWhat really makes an image heavy: pixels, format, quality. JPG vs WebP vs AVIF sizes, quality settings that work, HEIC to JPG, and photos for email.Read the guide Wi-Fi QR code not working: why it says “incorrect password” and how to fix itWhy a Wi-Fi QR code says incorrect password: unescaped ; and :, accented characters, hidden networks, WPA3. How to make one that works and test it first.Read the guide

See all guides

Why files should be processed in the browser, not on a server

Classic tool websites all work the same way: you upload a file, a server processes it, and you download the result. Somewhere in that round trip your document leaves your machine, gets copied onto hardware you do not control, and stays there for however long the operator decides. For a holiday photo, fine. For a contract, a payslip, a medical report or a client file, not fine at all.

Modern browsers no longer need that middleman. WebAssembly lets them run the same document engines that used to live only in desktop software, at close to native speed, without asking anyone's permission. Utiliobox is built on that: the engine downloads once, and from then on it works with files that never leave your device.

Three practical consequences. Privacy: there is no remote copy to delete and no retention policy to read. Speed: nothing has to crawl up a slow connection and back down again. And availability: once the page has loaded, you can switch off Wi-Fi and keep working.

What we collect and what we don't

We collect nothing from your documents, because technically they never reach us. What is measured is aggregate site usage and, once you enable advertising, the ad provider's cookies — all of it spelled out plainly in the privacy notice and the cookie policy. Ads stay switched off until you accept them.

Genuinely free, no catch

No accounts, no daily file quota, no watermark stamped on your result, no “pro” tier holding the basics hostage. The site is paid for by unobtrusive advertising, which is why the cookie banner exists at all. If a tool ever cannot do something, its own page will say so rather than leaving you stranded.

Frequently asked questions

Is nothing really uploaded?

Really. You can prove it yourself in ten seconds: open any tool, let it load, turn off Wi-Fi or mobile data, then process a file. It keeps working, because the work is done by your browser, not by a server of ours.

Do I need an account or an install?

No. No accounts, no confirmation emails, no software to install. Open the tool's page and use it.

Can I use this on a phone?

Yes. The tools are designed for phones from the start rather than shrunk at the end: large controls, thumbnails you can reorder with buttons instead of fiddly dragging, and nothing that overflows the screen. Memory is the limit on a phone, so very large files will do better on a computer.

Which browsers are supported?

Recent versions of Chrome, Edge, Firefox, Safari and Opera, on desktop and mobile. If your browser cannot run one of the engines, the tool says so in plain language instead of hanging.

Is there a size limit?

Your device's memory sets the limit, not us. Every tool states its recommended size before you start; for the PDF toolbox it is around 100 MB and 500 pages on an ordinary laptop.

Are more tools coming?

Yes, that is the plan. The site is built to keep adding tools, each with its own page in English and Spanish. Whatever is live always shows up in the list above and in the header menu.