Notes from the cleaning room.
Guides, comparisons and stories about removing ads from study PDFs — Wuolah, StuDocu, Z-Library and the rest of the ad-riddled document ecosystem.
Gulag Cleaner not working? What to check and how to clean your PDF anyway
If Gulag Cleaner isn't working, won't load or returns an odd PDF: the seven usual causes, how to fix them and how to clean your Wuolah PDF for free.
Gulag Cleaner on mobile: how to clean a Wuolah PDF from Android or iPhone
Gulag Cleaner works on your phone, nothing to install. How to clean Wuolah and StuDocu PDFs on Android and iPhone, and where the clean file ends up.
Gulag Cleaner CLI (Python) vs the web version: what they share and which to use
Gulag Cleaner exists as a Python command-line tool and as a web app. Installation, options, a side-by-side table and when each one makes sense.
Wuolah without ads: every way to get ad-free notes (and which one is free)
The real options for ad-free Wuolah notes: the platform's paid download, cleaning the PDF for free with Gulag Cleaner, and what isn't worth it.
What is Gulag Cleaner? The free cleaner that strips ads from study PDFs
A clear introduction to Gulag Cleaner, the free in-browser PDF cleaner built for students drowning in Wuolah and StuDocu sponsored pages.
How to remove Wuolah ads from any PDF (free guide, 2026)
Step by step: remove Wuolah covers, banners and inserted sponsored pages from any downloaded PDF using Gulag Cleaner.
Clean StuDocu PDFs: remove the sponsored pages in one click
StuDocu PDFs come loaded with ads. Learn how Gulag Cleaner detects and removes them locally, without uploading anything.
Gulag Cleaner vs Adobe, iLovePDF and Smallpdf: the honest comparison
How Gulag Cleaner compares with Adobe Acrobat, iLovePDF and Smallpdf when it comes to removing ads and sponsored pages from PDFs.
Why every student's PDFs need a cleaner
The hidden cost of ad-filled study PDFs — focus, ink, file size — and how a one-click cleaner fixes it.
The open-source story behind Gulag Cleaner
From a Rust tool to a web app in the browser — the story and the philosophy behind Gulag Cleaner.