How our tools work, how we write and how we make money
Updated October 2026
This page explains in plain language what happens to your file, what each tool really does, how we decide what to publish, and how the site pays its bills.
What happens when you use a tool
You open a tool and choose a file. The file is read by your browser from your own device.
Code running in the page does the work. The tools are written in JavaScript and WebAssembly, and the heavy lifting is done by well-known open-source libraries: pdf-lib to create and edit PDF files, PDF.js to draw pages, qpdf for passwords, encryption and repairs, Tesseract for OCR, mammoth to read Word documents, pdfmake and html2canvas to lay out PDF pages, the open fonts Carlito, Caladea, Liberation and Poppins to draw Word, Excel and PowerPoint text, SheetJS for spreadsheets, PptxGenJS for presentations, heic2any for iPhone photos and JSZip to bundle several results into one download. Background removal (in Remove Background and the Passport Photo Maker) uses the open-source U²-Net model by Xuebin Qin and colleagues (Apache 2.0), run by our own code in WebAssembly.
The result is created in your browser’s memory and handed to you as a download. We never receive the file.
When you close or reload the tab, the working data is gone. The one exception is Continue with: when you send a result straight to another tool, the file is kept briefly in your browser’s own storage so the next page can open it, and removed as soon as the next page opens it (or, if it is never opened, the next time you visit any page here after 15 minutes).
The libraries are served from our own site, not from a third-party network, and are downloaded the first time a tool needs them (the OCR language data is 1–3 MB per language and is then cached). Downloading code is separate from handling your documents: your documents are not part of those requests.
Each library is used unchanged under its own open-source licence, and its authors’ copyright notices are kept. The complete list of licences and notices is in our open-source notices. The code that connects these libraries and turns them into each tool on this site is our own.
What this means for you
Privacy: because the file does not leave your device, we cannot read it, keep it or lose it. You can check this yourself by opening your browser’s developer tools and watching the Network tab while you run a tool: there is no upload of your file.
Speed: there is no upload or queue. The speed depends on your device and on the size of the file.
Limits: a phone has less memory than a server. Very large files, or documents with hundreds of scanned pages, may be slow. Splitting the document into parts helps.
Honest trade-offs: a browser can do a lot, including OCR, but not everything a desktop suite can. We do not offer PDF/A conversion, translation or batch processing of hundreds of files, for example.
What each tool does, and its main limit
Each tool page lists all its limits and fixes for common problems. The last column below is the first limit listed on that page, so you can spot a mismatch with your task early.
Crop photos freely or to square, passport and other ratios.
Cropping cannot add pixels. A small crop from a small photo stays small; check the pixel size if a form sets one.
Our editorial standards
Everything on this site is written to help someone finish a real task. Our rules:
We check before we describe. Before a guide or a tool page says a tool can do something, we check it against how the tool actually behaves. If a guide and the tool disagree, the guide is wrong and we fix the guide.
We state limits plainly. A page that only lists strengths wastes your time. Each tool page has a section called Limits to know before you start and another called If something goes wrong.
We do not promise results we cannot control. We do not say a tool will make every file smaller, convert every layout perfectly or make a signature legally binding.
We do not copy. Guides are written for this site, based on how these tools behave.
We separate advice from legal or professional advice. Notes about signatures, redaction and confidentiality are practical guidance, not legal advice.
We update and correct. Pages show an updated date. If you find an error, use the contact form. We correct factual mistakes quickly and change the updated date when we do.
How we make money
The tools are free. The site earns money from advertising, currently shown by Google AdSense. We want to be direct about how that works:
Advertising is our only source of income. We do not sell your data, charge for tools or take payments from the companies whose products we mention.
Advertisers do not pay to appear in our guides, and no one pays us for a favourable comparison. Links to other companies are plain references, not paid placements.
Your documents are never used for advertising. They are not uploaded, so they could not be.
You choose. The cookie banner lets you accept personalised ads or reject them. If you reject, Google is asked to show only non-personalised ads. Google’s code is still loaded on our pages, as described in the privacy policy, and you can change your choice later in Cookie settings in the footer.
We keep ads separate from the tools and guides, label them as advertisements, and never ask you to click them.
Ads keep these tools free. Our advertising partner (Google) may use cookies and similar technologies. Your documents are never uploaded or shared. Accept for personalised ads (18+ only), or reject for non-personalised ads only. Privacy Policy