About PDF Annotator
PDF Annotator is a free, browser-based PDF editor built and run by one person: me, Stanislav Mashkin, a software developer in London. It opens a PDF in a tab, lets you highlight, sign, fill and draw on it, and gives the annotated file back — without an account, a subscription, a watermark, or a copy of your document on anyone's server.
This page exists because a tool that asks you to hand over a contract or a medical form should be willing to say who is behind it.
Who makes it
I build web software independently rather than inside a company, mostly on the front end. PDF Annotator is one of a handful of small tools I run on my own — each of them the kind of single-purpose utility that used to be a desktop app and has no business requiring a login today.
The work is published under STANMASH LTD, a private company limited by shares, registered in England and Wales on 14 July 2026 under company number 17337841. The registered office is at Stoney Works, 8 Stoney Lane, London SE19 3BD, United Kingdom. The Companies House record is public — the link above goes straight to it, no login needed. I'm the sole director, which is another way of saying that when something on this site breaks, there is exactly one person to blame.
Why it works the way it does
Most free PDF tools follow the same shape: you upload the file, a server does the work, you download the result, and a privacy page promises the copy is deleted in an hour. That's a reasonable engineering choice and a bad deal for the person with the document. The files people actually annotate are the ones they'd least like to hand over — a signed lease, a diagnosis, an offer letter, a client's contract under NDA.
So this one doesn't upload. Your PDF is read and rendered inside the browser tab, the annotations are drawn there, and the export is assembled there too. The site itself is a set of static files with no backend to receive a document even if it wanted one. You can check the honest way: open your browser's network tab, load a PDF, and watch for a request carrying it. There isn't one. Disconnect from the network after the page has loaded and the editor keeps working.
The trade-offs are real and worth stating. Everything happens in your tab's memory, which is why very large scans are out of scope. Nothing syncs between your laptop and your phone, because there's no account to sync through. The exported PDF is what travels — and it opens anywhere, in any reader, with no dependency on this site continuing to exist.
How it's paid for
It isn't, currently. There is no paid tier, no advertising, no affiliate links in the tool, and no analytics profile being sold on. Running a static site costs very little, and the tool is genuinely finished for the job it does, so there's nothing to recoup.
If that changes I'll say so on this page rather than quietly introducing a limit — and the honest version of that promise is that whatever is free today stays free. I'd rather write that down in public now, while it's easy to hold myself to.
What's on the site
The editor lives on the home page — there's nothing to install and nothing to sign up for. Beyond that, a few pages go into individual jobs in more detail: highlighting a PDF covers text selection and colours, taking notes on a PDF covers sticky notes and the study workflow, and the PDF annotation app overview compares browser tools, desktop software and cloud services honestly, including the cases where a cloud tool is the better answer.
Other things I build
Same idea, different file formats. If a converter or a small utility is what you're after: CSV to PDF turns spreadsheet exports into printable tables, WAV to MP3 compresses audio without an upload, and Website Feedback Tool collects review comments directly on a live page. All built the same way, by the same person, with the same allergy to signup forms.
Getting in touch
Bugs, feature requests, a PDF that renders wrong, or a question about how something is stored — email stasmashkin.art@gmail.com or find me on X as @mrstanmash. It's me reading it, so a broken document attached to a short description gets fixed faster than a support ticket ever would.
If you found a security issue specifically, that one has its own route: security.txt.