A browser-based PDF editor and annotator built for academics. Edit pages, add LaTeX equations, and mark student work entirely on your device — no upload, no sign-in.
A short overview of annotation, comments, and basic PDF editing.
An example marking workflow using mark stamps, feedback, and the comment library.
How to bulk-download Blackboard assignments and mark them faster with Annotarium.
A growing set of tools for marking work, adding feedback, and editing PDFs.
Add equations and symbols to your PDFs using LaTeX.
Set up marking schemes with question-level totals.
Save and reuse comments, feedback snippets, and images.
Pen, highlighter, shapes, arrows, and stamps.
Add, delete, or rearrange pages. Merge PDFs or insert templates.
Runs in any modern browser with no installation. Optimized for desktop; tablet and pen support improving.
Save PDFs and annotations separately, so work stays fully editable. Reopen and continue where you left off.
Protect annotated work with password-encrypted .annot files (PBKDF2 + AES-256-GCM).
Exploring AI-assisted grading, handwriting recognition (OCR), and feedback tools.
Annotarium is designed so your documents stay in your browser.
Annotarium is actively developed and continues to evolve based on academic use.
Dedicated guides for the most common Annotarium workflows.
PDF marking, LaTeX feedback, rubrics, and reusable comments — built for the academic workflow.
Open the Blackboard ZIP and mark every student in one session — no upload, no sign-in.
Step-by-step guide to adding properly typeset LaTeX equations directly to any PDF.