The 7 rules of a good summary
- Accurate — nothing the source doesn't say; claims kept at the same strength.
- Main points only — the thesis and supporting ideas, not every example.
- Proportional — parts that take more space in the source usually deserve more space in the summary.
- Neutral — no opinion unless you're asked for an evaluation.
- Your own words — paraphrase; quote only key terms or phrases.
- Self-contained — understandable without the original.
- Short — if it isn't much shorter than the source, it isn't a summary.
The 5-step method
- Understand the wholeRead or skim the full text once. Identify its purpose and audience.
- Find the main pointsOne per section or paragraph. Highlight the thesis and conclusions.
- Cut the detailsExamples, anecdotes, repetitions, digressions go. Keep numbers that support main points.
- Write in your own wordsStart with the main idea, then the supporting points in logical order.
- Check against the sourceEvery statement true? Anything important missing? Same strength of claims?
How long should a summary be?
| Source | Typical summary |
|---|---|
| Article (1-2 pages) | 3-5 sentences |
| Report (10-20 pages) | 150-300 words |
| Research paper | 200-400 words, structured |
| Book | 500-1,000 words, by part or chapter |
| Any document, for a message | 3-5 key points |
Example
Original (excerpt): “Although remote work increased individual productivity in our survey of 1,200 employees by an average of 9%, managers reported more difficulty onboarding new hires, and team-level innovation metrics declined slightly over the two-year period.”
Weak summary: Remote work is good for productivity. — loses the trade-off, the numbers and the scope.
Good summary: A two-year survey of 1,200 employees found remote work raised individual productivity by about 9%, but made onboarding harder and slightly reduced team innovation.
Common mistakes
- Adding interpretation (“which proves that…”) the source doesn't make.
- Copying sentences instead of condensing them.
- Starting with details instead of the main idea.
- Losing the numbers that make a finding meaningful.
- Ignoring the conclusion or the limitations.
Checking an AI-written summary
AI tools apply these rules quickly, but you are still the editor. Check: Is the main idea correct? Are numbers right (open the cited page)? Is anything important missing — ask the tool “What did you leave out?” Are claims stronger than in the source? The PDF summarizer gives page references precisely so this check takes a minute.
Frequently asked questions
What is the difference between a summary and a paraphrase?
A paraphrase restates a passage in different words at similar length. A summary condenses the main ideas of a whole text into a much shorter form.
Should a summary include my opinion?
No, unless you are asked for a critical summary or review. Keep evaluation separate from the summary.
How do I summarize in one sentence?
Combine the topic, the main claim and the key support: “[Source] argues that [claim] because [main reason/evidence].”
Can AI write summaries for school?
It can help you understand texts. Many schools forbid submitting AI-written work as your own — use it to learn, and write the final summary yourself.