Study the reading - with answers you can check.
Sidenote is a browser extension (Chrome and Firefox) that reads the lecture PDF, slide deck or textbook chapter you have open and helps you get through it: summaries, plain-English explanations, revision glossaries, and chat. Every answer cites the exact passage, so you can check it against the source before it goes anywhere near your essay.
Free tier forever · Lecture PDFs, slides & textbook chapters
Re-reading feels productive but fades fast. In study after study, testing yourself on the material beat re-reading it, and the gap widens with time: the advantage of retrieval practice was largest a week after learning, exactly when the exam is.
Test yourself instead of re-reading: self-testing beat re-reading 1 - and its advantage was largest a week after learning 2.
The reading list doesn't care that you have four other modules.
Forty pages of assigned reading, a slide deck that assumes the lecture explained itself, and a textbook chapter written for someone who already knows the subject. A generic chatbot will answer anything about them, confidently, whether or not the answer is actually in the text - and you can't hand in “the AI said so”.
Sidenote is built for trust: it summarizes and explains, but every claim is pinned to a passage you can jump to and check. The reading stays the source of truth - which is exactly what your grader wants cited.
How Sidenote works on your reading.
Open the reading - or drop it in.
Works on lecture PDFs and articles your browser can open, with nothing to set up. For files, drag the PDF, Word document or PowerPoint deck onto the side panel; scanned handouts get OCR'd first.
Summarize, explain, or build a glossary.
Get the chapter's summary, highlight the paragraph that lost you for a plain-English rewrite, or one-click a revision glossary of every term.
Click a citation, land on the passage.
Every answer is grounded in a quoted passage. Click the chip and Sidenote scrolls to the exact sentence and highlights it - ready to reference properly.
Revising a whole topic? The one-click glossary builder turns a chapter into a self-test list, and every citation takes you back to the passage. Just need the gist of an article? See the AI summarizer.
Get through the reading, not just around it.
“Explain this like I'm new to the topic.”
Highlight the paragraph that lost you and Sidenote rewrites it in plain English - with the original passage still one click away.
“Turn this chapter into a revision glossary.”
One click builds a glossary of every term in the chapter, each definition linked to the passage where it's actually taught.
“Summarize this week's reading.”
A grounded summary of the assigned chapter or article, with every claim cited, so you know what to read closely and what to skim.
“Where does the textbook actually say that?”
Ask, click the citation, and land on the exact sentence - so you can quote and reference the source itself in your essay.
“What's the difference between these two concepts?”
Sidenote answers from the document in front of you and pins each side of the comparison to the passage that defines it.
“Did I understand this right?”
State your reading of a passage and ask. The answer quotes the text back at you, so you revise from the source, not a guess.
Answers you can check before you cite them.
Most AI study tools ask you to trust the summary. Sidenote doesn't: every claim in every answer is checked server-side against the passages retrieved from your document, verbatim. If a quoted line can't be found in the source, the citation is dropped rather than shown.
Click a citation and Sidenote scrolls to the exact sentence and highlights it. That's the difference between “sounds right” and a passage you can quote, page and all, in your own work.
Built to fit a student budget.
The free tier is free forever: 3 documents, 10 standard summaries, 10 explanations, 3 glossary builds and 10 cited chat turns a month - enough for a week's core reading. The 7-day Pro trial is one click and an email, no card, and paid plans start at £10/month if you outgrow it.
Common questions from students.
Read it once. Actually get it.
Add Sidenote to your browser, open the lecture PDF, and ask it anything. Free tier forever, opt-in 7-day Pro trial, no card required.
Free tier forever · Works on lecture PDFs, slides and chapters