Most free online tools come with a catch. You upload your file, wait for a server to process it, and hope the site deletes it afterwards. Cromagnon works differently. It offers free private online tools that run inside your browser, so your files stay on your own device.
This guide explains what Cromagnon is, what you can do with it, and how its privacy model works. By the end, you will know if it fits the way you work.
Why most online file tools feel risky#
Think about the last time you merged a PDF online. You probably dropped a contract, a payslip or a school report onto a stranger's website. That file then travelled to a remote server before you saw the result.
This habit is convenient, but it creates three problems:
Privacy: your file sits on someone else's computer.
Cost: many tools add watermarks, daily limits or a monthly fee.
Friction: you often need an account just to edit one page.
We built Cromagnon to remove all three. The software comes to your browser, and your files stay where they are.
What is Cromagnon?#
Cromagnon is a collection of free, browser-based workspaces for everyday files. It includes 10 full studios and more than 60 quick tools. Each studio opens real file formats, saves your work automatically and exports to the formats other people use.
You do not need an account. You do not need to install anything. Open the site, drop in a file and start working. If you prefer, you can also install Cromagnon as an app and keep working offline.
The ten studios at a glance#
Each studio is a complete application, not a single-trick converter. Here is what they do:
PDF Studio: annotate, sign, redact, merge, split, compress and convert PDFs. It also runs OCR, which makes scanned pages searchable.
Document Studio: write, format and export real Word (DOCX) files.
Excel Studio: edit spreadsheets with working formulas.
CSV Studio: clean, reshape and chart data files of any size.
Presentation Studio: build, present and export slide decks.
Image Studio: grade, compress and convert photos, including WEBP and AVIF.
Study Studio: make flashcards with the FSRS memory model and eight study modes.
Citation Studio: build reference lists in APA, MLA, Chicago, Harvard, IEEE and 13 more styles.
Math Studio: solve maths problems with every step shown.
Invoice Studio: create professional invoices and quotes in minutes.
Two more are coming soon: Resume Studio and Contract Studio.
Three things that make Cromagnon different#
Plenty of sites offer one clever tool. Cromagnon aims higher, and three details set it apart.
First, everything lives in one place. Instead of juggling five websites for PDFs, Word files, spreadsheets, slides and flashcards, you open a single site. The layout, shortcuts and look stay familiar from studio to studio.
Second, it uses real file formats. The studios open and save genuine DOCX, XLSX, PPTX and PDF files. As a result, you can share your work with anyone, whatever software they use.
Third, your work is protected. Every studio autosaves in your browser and offers undo. So a closed tab or a slow day does not cost you an afternoon of effort.
Quick tools for small jobs#
Sometimes you only need a fast fix. The quick tools page covers those moments. Popular picks include the JSON formatter, the word counter, the QR code generator and the password generator.
Developers get extra value here. The JWT decoder and regex tester make no network requests. As a result, you can paste a token or a customer record without worry.
How our free private online tools protect your files#
Cromagnon processes files on your device. The page loads once, and then your browser does the work. Your file contents are not uploaded unless you choose to sync a deck, publish it to the library or share it with a class.
For security, the site records only file names, sizes and types. A free account is optional. It adds sync between devices and 50 MB of cloud files.
This design has a useful side effect. Because nothing travels across the internet, tools open quickly, and they keep working on a plane. That is why browser-based tools like these suit sensitive documents so well.
Who uses Cromagnon?#
Different people use the same toolkit in different ways:
Students turn lecture PDFs into flashcards, check maths step by step and build bibliographies.
Teachers share decks with a class code and write worksheets as real Word files.
Office workers sign contracts, fix spreadsheets and merge PDFs without sending company files elsewhere.
Developers format JSON and test patterns safely.
Creators and sellers grade product photos and compress images for the web.
A free alternative to paid subscriptions#
Many people pay $10 to $25 a month for each tool they use. Cromagnon is free to use, with no watermarks and no daily limits.
For example, Study Studio imports Anki and Quizlet decks. It also uses FSRS, a modern spaced repetition model that predicts when you will forget a card. In short, you get the study power without the monthly bill.
We are also honest about the future. If a paid plan ever arrives, it will only cover extras that cost money to run. What is free today stays free.
Why the name Cromagnon?#
Cro-Magnons were early modern humans who lived in Europe during the Upper Paleolithic. They painted hands on cave walls, counted on bones and shaped stone into tools.
The work has not changed much. We still write, count, draw and share. Cromagnon simply makes the tools free, private and quick. Humans have always been toolmakers, and these are tools for the modern human.
How to start in three steps#
Open a studio or drop a file on the homepage. The right studio opens for you.
Do the real work. Your changes save automatically in your browser, and undo is always there.
Export or install. Save to PDF, DOCX, XLSX, PPTX, CSV or PNG, or add Cromagnon to your device and work offline.
Frequently asked questions#
Is Cromagnon really free?#
Yes. Every studio and tool is free, with no watermarks and no daily limits.
Do I need an account?#
No. Everything works without signing up. An account only adds sync, the public deck library and classes.
Does Cromagnon work offline?#
Yes. Install it from your browser, and the studios you have opened keep working without internet.
Which languages does it support?#
Study Studio supports 107 languages. Every studio also handles right-to-left scripts such as Arabic, Hebrew, Persian and Urdu.
Try Cromagnon today#
Stop uploading your life to get simple things done. Open the studios, pick a tool and see how fast private work can feel. Missing a feature or found a bug? Contact us and tell us what to build next.
Cromagnon — tools for modern humans.