Who runs Altto
Altto is an independent website run in the UK. It isn’t part of a larger company, it has no paid tier, and you don’t need an account for any of it. If something doesn’t work, or there’s a tool you’d find useful, the Contact page goes straight to the person who runs it.
Made in Britain
Altto is made and run in the UK. That shows in small ways: the site is written in British English, prices are in pounds, and some tools exist because UK users need them, like the Making Tax Digital checker and spreadsheet, the UK passport photo checker and the guide to UK e-invoicing.
The tools work the same wherever you are, though, and visitors from all over the world use them. Because your files are processed on your own device, it doesn’t matter where Altto’s web servers are: your documents never go to any of them.
Tests, games and guides: how they are made and checked
The tests, games, flashcards and guides on Altto are written for Altto, not copied from other sites, and kept up to date as the rules and sources change. Each guide shows the date it was last checked.
Tax and money guides are checked against the GOV.UK and HMRC pages they are based on, and the guide names the page and the date it was checked. They explain the rules in plain English; they are not tax advice, so check your own position with HMRC or an accountant.
Life in the UK practice questions are Altto’s own unofficial questions on the topics in the official handbook. They are not the real test questions. GCSE flashcards are written to follow the AQA GCSE specifications, and most of the content suits Edexcel, OCR and Eduqas too. IQ, brain age and personality tests are for fun and self-knowledge, not a clinical or professional assessment.
Altto is written and maintained with the help of AI tools. Where a guide states a figure, date or rule, it is checked against the official source named on that page before it is published. If you spot a mistake, tell us and we will correct it and note the change on What’s new.
Where Altto has been featured
Altto is listed in TechTippr’s 101 Most Useful Websites, under PDF, image and everyday browser tools.
How Altto works
Most free file sites ask you to upload your file to their server, wait while it’s processed, then download the result. Altto works the other way round. When you open a tool, your browser downloads the tool itself: the code that does the job and, for the AI tools, a model file. From then on, your file is opened and processed by that code on your own device, and the result is saved straight back to it.
That means:
- Your files aren’t uploaded. There’s no server receiving them, so Altto can’t see, copy or keep them.
- There are no queues or daily limits. Your own device does the work, so there’s nothing to ration.
- Speed depends on your device. A recent computer handles big files and the AI tools quickly; an older phone takes longer.
If you’d like to check for yourself, here is how, in Chrome, Edge or Firefox on a computer:
- Open the tool page, for example Compress PDF.
- Press F12 (or right-click the page and choose Inspect), then click the Network tab.
- Click the bin or clear icon in that tab so the list starts empty.
- Choose your file and run the tool as normal.
- Look through the list. You’ll see small requests for the page’s own scripts and fonts, but nothing carrying your file going out. A request that uploads a file would show your file’s name or size under the request details, and there won’t be one.
You will see a few other requests, none of which carry your file: the tool’s code and fonts from altto.co.uk; for AI tools, a model file from altto.co.uk or models.altto.co.uk (or Hugging Face as a back-up); Google’s consent message and Google ads (personalised only if you agree); Google Analytics and Microsoft Clarity, only if you agree; Cloudflare’s cookie-free page counter; and short notes to Altto’s own counter saying which tool was used and whether it worked. The Privacy Policy lists exactly what each one sends.
The site does count visits and see which tools are used, and it may show ads from Mediavine, which use cookies. None of that includes your files. The Privacy Policy explains exactly what’s collected and how to switch it off.
What’s on the site
- PDF tools: merge, split, compress, rotate, crop, sign, unlock and watermark PDFs, number their pages, and more.
- Converters: PDF to and from Word, Excel, PowerPoint and images, plus HEIC, WebP, PNG and JPG conversions.
- AI tools that run on your device: a background remover, an image upscaler, speech to text, document summaries and translation.
- Everyday tools: QR codes, barcodes, passwords, a word counter, an invoice generator and others.
You’ll find them all on the Tools page, with practical how-to articles in the Guides. Each tool’s own page has tips for getting the best result and answers to common questions.
What Altto can’t do
Because everything runs in your browser, a few things are harder than on a big server. Very large files can be slow on older devices, scanned documents rely on text recognition that works best on clear scans, and converters such as Word to PDF rebuild a document rather than copying its exact layout. Each tool’s FAQ explains its own limits. Altto is built for everyday documents, not as a replacement for professional document services.
Why it’s free
Altto is paid for by advertising, rather than by per-file fees. There’s no daily limit designed to push you towards a paid plan, because there isn’t one.
How Altto makes money
Being open about this matters, so here is the full list:
- Advertising. Altto shows ads through Mediavine. In the UK and EU they appear only with your cookie consent. They never change what a tool does with your files.
- Nothing about your files. Files and text are processed on your device and never uploaded, so there is nothing for Altto to sell.
If this ever changes (for example optional paid extras for heavy users), the free tools on this site will stay free and this page will say so.
How we test
Every tool is tested with real files, not just by checking the page loads:
- Every tool, end to end. An automated test opens each tool in a browser, gives it a real file, presses the main button and then opens what comes out to check it: the pages and text in a PDF, the size and format of an image, what’s inside a Word, Excel or PowerPoint file. It also opens each tool at phone size to catch layouts that don’t fit and errors in the page.
- Awkward files on purpose. The test files include the kinds that trip tools up: scanned PDFs, password-protected PDFs, newer iPhone photo formats, and Publisher files of different ages and layouts.
- Daily checks. The main tools are run on real test files every day, at desktop and phone sizes. A change that fails a test doesn’t go live, and every change is checked on the live site after it’s published.
- Published accuracy figures. PDF to Word is scored on 200 public test PDFs from an open benchmark. The benchmark page shows the results, how they were scored and how to repeat them.
- Sources for facts. Guides that state rules, dates or product details are being given a Sources list linking the official page, such as GOV.UK or Microsoft’s own support pages.
New tools, improvements and fixes are listed on the What’s new page.