
SpecialistOffers broad general reasoning and document upload capabilities, but lacks specialized academic indexing and citation databases.

SciSpace records 4,464,111 monthly visits with +8.6% month-over-month growth and Freemium pricing. Side Reader records 355 monthly visits with -36.5% growth and Freemium pricing.
Read and chat with PDFs right beside ChatGPT, Claude and DeepSeek.
| Dimension / Metric | ![]() | |
|---|---|---|
| Official Domain | scispace.com | side-reader.com |
| Pricing Model | Freemium | Freemium |
| Monthly Visits | 4.46M (4,464,111) | 355 (355) |
| MoM Traffic Delta |
| +355.38K (+8.6%) |
| -204 (-36.5%) |
| Primary Market & Share | 🇺🇸 United States (13.2%) | 🇻🇳 Vietnam (100%) |
|---|
| Direct Visits / mo | 1.32M | 149 |
|---|
| User Rating | 4.6 | 2.4 |
|---|
| Supported Platforms | Website | Website |
|---|

AI research platform for reading, understanding and writing scientific papers
Open or upload a paper and ask questions, get plain-language explanations of highlighted passages, and pull out methods, results and limitations conversationally.
Search a large scholarly index spanning Google Scholar, PubMed and arXiv, then generate structured literature reviews and related-work sections from what you find.
An AI Writer for drafts, a paraphraser for academic tone, and a citation generator that formats references in popular styles.
Turn tables and results in a paper into structured data, and check whether a manuscript reads as AI-generated with a built-in detector.
Read and chat with PDFs right beside ChatGPT, Claude and DeepSeek.
PDFs render directly in the sidebar next to the chat, so your document and the AI conversation are visible at the same time.
Summarize a whole document, translate it, or have passages explained in simpler terms using the AI you are already signed into.
Built-in buttons cover the common actions, and you can edit their prompts to make the AI respond in the format and tone you need.
Ask about charts, scans or regions that cannot be selected by taking a screenshot question instead.

SpecialistOffers broad general reasoning and document upload capabilities, but lacks specialized academic indexing and citation databases.


Free / Open-sourceProvides a massive free index of scholarly literature with citation graphs, but lacks built-in interactive paper reading assistants.


Provides evidence-based answers extracted directly from peer-reviewed papers, though less of an all-in-one reading workspace.
#3A free, AI-powered PDF editor for every device
AI sidebar and browser agent for reading, writing and research

Bilingual AI translation for websites, documents, video and images
Stronger automated data extraction and systematic review synthesis, but less focused on interactive PDF annotation than SciSpace.

Free AI-powered PDF editor, converter and reader for every device
SpecialistFocuses heavily on assisted academic drafting and autocomplete, whereas SciSpace centers more on reading and analysis.

One AI assistant that plugs ChatGPT, Claude and Gemini into every tab

Cross-platform PDF editing with GPT-powered AI for reading, translating, and signing documents
Chat with any PDF, video, or website and get cited answers in seconds
SpecialistOffers broad general reasoning and document upload capabilities, but lacks specialized academic indexing and citation databases.
Free / Open-sourceProvides a massive free index of scholarly literature with citation graphs, but lacks built-in interactive paper reading assistants.
Provides evidence-based answers extracted directly from peer-reviewed papers, though less of an all-in-one reading workspace.
AI sidebar and browser agent for reading, writing and research
Bilingual AI translation for websites, documents, video and images
Stronger automated data extraction and systematic review synthesis, but less focused on interactive PDF annotation than SciSpace.
Free AI-powered PDF editor, converter and reader for every device
SpecialistFocuses heavily on assisted academic drafting and autocomplete, whereas SciSpace centers more on reading and analysis.
One AI assistant that plugs ChatGPT, Claude and Gemini into every tab