Summarize PDF picks out the sentences that best represent a document and returns them as a short reading list, in the order they appear, each marked with the page it came from. Choose five, ten, twenty or forty sentences, add a list of the document's key terms, and copy the result or download it as a Markdown file.
The ranking is TextRank: every sentence is compared with every other by the words they share, weighted so that words common across the whole document count for less, and the sentences most similar to the rest of the text score highest. That scoring, the sentence splitting and the text extraction all run as JavaScript in your browser. The PDF is never uploaded, and the summary exists only on your device until you save it.
This is extraction, not writing. Every sentence in the summary appears word for word in the original, so the result reads as a set of quotes rather than a fluent abstract, and it works best on prose such as reports, papers and long articles. Scanned PDFs have no text to rank; run OCR PDF on them first. The stop-word list and suffix stripping are English, so other languages rank less reliably.
How to use Summarize PDF
- 1Click Select file, or drop the PDF onto the page. The tool works on one document at a time.
- 2Under Length, pick Brief (5 sentences), Standard (10), Detailed (20) or Long (40). Standard is the default.
- 3Leave List the key terms and Note the page each sentence came from checked, or untick either one.
- 4Click Summarize and wait while the text is extracted, split into sentences and ranked.
- 5Read the summary in the preview, click Copy to put it on the clipboard, or click Download to save it as a Markdown file.
Frequently asked questions
- Does this use AI to write the summary?
- No. It uses TextRank, a graph algorithm: sentences are scored by how much vocabulary they share with the rest of the document, and the top-scoring ones are returned unchanged. No language model is involved and nothing is generated or paraphrased.
- Is my PDF uploaded to a server?
- No. Text extraction, sentence splitting and ranking all run in your browser with JavaScript. The file never leaves your device, and the summary is only saved where you choose to download it.
- Why does the summary read like a list of quotes rather than a paragraph?
- Because it is one. Every line is a sentence lifted word for word from the document, kept in its original order. That makes it a reliable index of what the document says, but it will not join ideas together the way a human-written abstract would.
- It says no readable sentences were found. What is wrong?
- The PDF has no text layer, which usually means it is a scan or a photo of a page. Run it through OCR PDF first to add searchable text, then summarize the result. Headings, tables and fragments shorter than five words, such as captions, are also skipped, so a PDF made only of those will produce nothing.
- What are the key terms, and why do some look cut off?
- They are the twelve words that carry the most weight across the document, measured by TF-IDF. Words are reduced to a stem before counting, so "processing" and "processed" are listed once as "process".
- Can it handle very long documents?
- Yes, up to the 100 MB file limit. Documents with more than 1,200 sentences are ranked in segments, and the sentence budget you chose is shared out in proportion to each segment's length, so the whole document is represented rather than only the beginning.