Elicit is purpose-built for exactly this workflow: you upload or search for papers, and it automatically extracts key findings, methods, sample sizes, and other structured data into a table you can scan and export for your literature review. It handles large batches of PDFs efficiently and lets you define custom columns so you pull out only what matters for your research question. NotebookLM is a strong alternative when you want to upload your own PDFs and ask open-ended questions across them in a conversational way. Claude Sonnet works well if you need to paste in full paper text and get nuanced, synthesized summaries with more analytical depth than a structured extraction tool provides. Perplexity is useful when you still need to discover papers rather than process ones you already have.