Submitting a research paper, thesis, dissertation, or journal manuscript is a major academic milestone. Before clicking the final submission button, however, researchers should perform one important quality check: plagiarism detection.

Even when a manuscript is written independently, it can contain unintended similarities with previously published research. Copied phrases, inadequate paraphrasing, missing citations, reused content, and incorrectly attributed ideas can all create academic integrity concerns.

That is why learning how to check plagiarism before submission is an essential part of preparing any academic manuscript.

A plagiarism check is not simply about obtaining a low similarity percentage. The real goal is to identify potentially problematic passages, verify citations, improve originality, and make sure that the manuscript accurately acknowledges previous research.

In this guide, we explain how to check plagiarism in a research paper before submission and what to do when a similarity report identifies matching content.

For additional support, explore our research support services to strengthen your manuscript. You may also find our guide on editing your research paper and guide on adding references helpful for preparing your final draft.

What Is Plagiarism in Academic Writing?

Plagiarism occurs when a person presents someone else's words, ideas, data, findings, or intellectual contribution as their own without appropriate acknowledgment.

Plagiarism can occur intentionally or unintentionally.

For example, a researcher may accidentally:

  • Copy a sentence from a journal article without quotation marks
  • Paraphrase a source too closely
  • Forget to cite a source after using its idea
  • Use another researcher's data without proper attribution
  • Reuse substantial portions of their own previously published work without appropriate disclosure
  • Include references but fail to cite the corresponding information correctly

Academic plagiarism is therefore broader than simply copying and pasting text.

A strong plagiarism check should examine both textual similarity and source attribution.

Why Should You Check Plagiarism Before Submission?

Checking your manuscript before submission gives you an opportunity to identify and correct potential problems before an editor or reviewer sees them.

A pre-submission plagiarism check can help you:

  • Identify accidental text overlap
  • Detect incomplete or missing citations
  • Find passages that require better paraphrasing
  • Review quotations and source attribution
  • Identify possible self-plagiarism
  • Improve the originality of your manuscript
  • Reduce the risk of editorial concerns or rejection
  • Strengthen your overall research integrity

How to Check Plagiarism Before Submission

The following process can help researchers conduct a more meaningful plagiarism review.

Step 1: Prepare the Final Version of Your Manuscript

Do not perform your final plagiarism check on an early draft if major changes are still expected.

First, complete your:

  • Introduction
  • Literature review
  • Methodology
  • Results
  • Discussion
  • Conclusion
  • References
  • Tables and figures, where applicable

Save a final working copy before running the check.

If you make substantial changes after receiving the plagiarism report, perform another check before submission.

Step 2: Choose a Reliable Plagiarism Detection Tool

Use a reputable plagiarism or similarity-detection system that can compare your manuscript against a meaningful collection of academic and online sources.

The quality of the database matters. A tool that searches only a limited selection of websites may not identify overlap with scholarly publications, conference papers, theses, or other academic material.

When selecting a plagiarism checker, consider:

  • Coverage of academic sources
  • Quality of the similarity report
  • Ability to identify matching passages
  • Source information
  • Options for excluding references or quotations
  • Privacy and manuscript confidentiality
  • Suitability for academic research

Researchers should also check whether their university, institution, or target journal recommends a particular system.

Step 3: Upload the Complete Manuscript

Whenever possible, check the complete manuscript rather than examining only a few paragraphs.

A full document provides a better picture of where similarities occur across different sections.

Pay particular attention to the:

  • Literature review
  • Introduction
  • Methodology
  • Discussion
  • Conclusion

The literature review may naturally contain more similarity because it discusses established theories and previous research. That does not automatically mean the section is plagiarized.

Step 4: Generate and Read the Similarity Report

After the plagiarism check is complete, review the report carefully.

Do not focus only on the overall similarity percentage.

A similarity score tells you that matching text has been detected. It does not automatically determine whether plagiarism has occurred.

For example, a manuscript may contain legitimate similarities because of:

  • Properly cited quotations
  • Reference entries
  • Standard academic terminology
  • Names of theories or models
  • Technical phrases
  • Common methodological descriptions
  • Titles of publications
  • Previously published material that has been appropriately disclosed

Therefore, the context of each match matters.

Step 5: Examine Every Significant Match

Open the sources identified in the similarity report and compare them with your manuscript.

Ask yourself:

  • Is this wording copied directly? If yes, determine whether it is properly quoted and cited.
  • Is the idea borrowed from another researcher? If yes, make sure the source is clearly acknowledged.
  • Is this a genuine paraphrase? If the sentence follows the original source too closely, rewrite it in your own structure and language while retaining the correct citation.
  • Is the match simply a standard phrase? If so, it may not require substantial revision.

This manual review is one of the most important parts of plagiarism checking.

Step 6: Improve Weak Paraphrasing

One common source of similarity is overly close paraphrasing.

Simply replacing a few words with synonyms does not necessarily create an original paraphrase.

For example, changing:

"Social media has significantly influenced communication among university students."

to a sentence that changes only a few words may still be too close to the original source.

Instead, understand the source's meaning first, put the source aside, and explain the idea using your own sentence structure and academic interpretation.

Always include a citation when the underlying idea comes from another source.

Step 7: Check Your Citations

A plagiarism review should also include a citation audit.

Check whether:

  • Every borrowed idea has an appropriate citation
  • Direct quotations have quotation marks where required
  • Citations correspond to entries in the reference list
  • References are complete
  • Citation formatting follows the required style
  • Sources have been attributed to the correct authors
  • Tables, figures, and data obtained from other sources are properly acknowledged

Correct citation is one of the most effective ways to demonstrate responsible use of existing research. For guidance, refer to our guide on adding references and guide on choosing the right citation style.

Step 8: Check for Self-Plagiarism

Plagiarism checking should not focus only on other people's work.

Researchers should also examine whether they have reused substantial content from their own previously published papers, conference proceedings, dissertations, reports, or other academic work.

This is commonly referred to as self-plagiarism or inappropriate text recycling, depending on the circumstances.

If previously published material is relevant to your new manuscript, follow the target journal's policies regarding disclosure, citation, permissions, and text reuse.

Never assume that content becomes automatically acceptable simply because you originally wrote it.

Step 9: Review the Methodology Carefully

Methodology sections can sometimes produce high similarity because researchers use established procedures and standardized technical language.

However, you should still distinguish between:

  • Standard terminology
  • A commonly used procedure
  • A directly copied description
  • Material taken from a published protocol or paper

When a specific method has been adopted from previous research, cite the original source appropriately.

Where necessary, explain how your implementation differs from or follows the published method. For guidance, refer to our guide on writing a methodology chapter.

Step 10: Review the References and Exclusions

Some similarity reports allow users to exclude bibliographic references or correctly formatted quotations.

These options can make the report easier to interpret, but exclusions should be used carefully.

Do not manipulate the report simply to produce a lower percentage.

The purpose of a plagiarism check is to identify potentially problematic content—not to make the similarity number look attractive.

A transparent and responsible review is more valuable than an artificially low score.

Before vs. After: Weak Plagiarism Check vs. Strong Plagiarism Check

Aspect Weak Plagiarism Check Strong Plagiarism Check
Document checked Only sections or early draft Complete final manuscript
Focus Only similarity percentage Individual matching passages
Paraphrasing review Not performed Each close match is revised
Citation verification Assumed correct Manually verified
Self-plagiarism Ignored Checked and addressed
Methodology review Overlooked Standard terminology distinguished from copied text
Report interpretation Percentage only Context of each match examined

What Similarity Percentage Is Acceptable?

There is no universal similarity percentage that guarantees that a manuscript is plagiarism-free.

Different journals, universities, publishers, and disciplines may apply different policies.

More importantly, the same percentage can represent completely different situations.

For example, a 15% similarity score could result from properly cited quotations, references, and standard terminology. Another paper with the same score could contain several paragraphs that closely reproduce an uncited source.

Therefore, researchers should not ask only:

"What similarity percentage is acceptable?"

A better question is:

"What do the matching passages represent, and have they been properly attributed?"

Always follow the specific requirements of your university or target journal.

What to Do If Your Similarity Score Is High

If the report identifies substantial overlap, do not panic.

Start by identifying where the similarity comes from.

  • If the text is copied without citation: Rewrite the passage in your own words and cite the original source. If the exact wording is necessary, use an appropriate quotation format according to the relevant academic style.
  • If the paraphrasing is too close: Read the source carefully, understand the concept, and rewrite the explanation using your own sentence structure and interpretation.
  • If the citation is missing: Add the appropriate citation and verify that the source appears correctly in the reference list.
  • If the similarity comes from references: Check whether your plagiarism software has an option to exclude the bibliography for analysis. Remember that this should be used for interpretation, not to conceal problematic overlap.
  • If the similarity comes from standard terminology: Determine whether the phrase is genuinely conventional in your field. Technical terminology does not automatically constitute plagiarism.
  • If the content comes from your previous publication: Check the target journal's rules regarding text reuse and self-citation. Disclose previous publication when required.

Should You Check Plagiarism More Than Once?

Yes.

A useful approach is to conduct a plagiarism check after completing the manuscript and then perform a final review after making revisions.

The process can look like this:

Draft manuscript → Similarity check → Review matches → Revise → Verify citations → Final similarity check → Proofread → Submit

This approach is more reliable than checking the document once and immediately submitting it.

Common Mistakes Researchers Make When Checking Plagiarism

Mistake Why It Hurts Your Review
Focusing only on the percentage The overall score is only one part of the report. Always investigate the actual matching passages.
Assuming every match is plagiarism Common terminology, references, properly cited quotations, and standard phrases may create legitimate similarity.
Changing a few words Replacing individual words with synonyms is not effective paraphrasing when the original sentence structure remains substantially unchanged.
Removing citations to lower similarity A citation should never be removed simply because it contributes to a similarity match.
Using multiple tools without understanding the reports Different tools use different databases and algorithms. Their results may therefore differ.
Checking only the introduction Similarity can occur anywhere in a manuscript. Review the entire document.
Forgetting previous publications Self-reuse should also be considered when evaluating manuscript originality.

Tips by Academic Discipline for Plagiarism Checking

  • Scientific Research Papers (Biology, Chemistry, Physics): Check methodology sections for copied experimental descriptions. Verify that data and figures are original or properly attributed.
    Example emphasis: "Review methods sections carefully. Standard procedures should be cited, not copied verbatim from previous papers."
  • Social Science Research (Psychology, Sociology, Education): Check survey instruments and questionnaire wording. Ensure theoretical frameworks are properly attributed.
    Example emphasis: "Verify that established theories and measurement instruments are correctly cited and not presented as original."
  • Humanities Research (History, Literature, Philosophy): Check quotations against original sources. Ensure primary source material is properly distinguished from secondary analysis.
    Example emphasis: "Verify all direct quotations and ensure that primary source interpretations are clearly distinguished from secondary scholarship."
  • Business and Management Research: Check industry reports and organizational data attribution. Ensure case study descriptions are original or properly cited.
    Example emphasis: "Review case descriptions and industry data sources. Ensure proprietary information is appropriately handled."

How to Reduce Plagiarism Risk While Writing

The easiest plagiarism problem to solve is the one you prevent during the writing process.

Develop good research habits from the beginning:

  • Keep detailed notes for every source
  • Record quotations separately from your own notes
  • Save complete bibliographic information
  • Cite sources while writing rather than waiting until the end
  • Use quotation marks for direct quotations
  • Paraphrase ideas genuinely
  • Keep your interpretation distinct from source material
  • Use a reference manager where appropriate
  • Review citations before finalizing the manuscript
  • Check for similarity before submission

For guidance on using reference management tools, refer to our guide on using Zotero for citation.

Final Pre-Submission Plagiarism Checklist

  • Have I checked the complete final manuscript?
  • Did I use a reliable similarity-detection tool?
  • Did I review the actual matching passages?
  • Have I properly cited borrowed ideas?
  • Are direct quotations clearly identified?
  • Have I genuinely paraphrased source material?
  • Have I checked for self-plagiarism?
  • Are tables, figures, and data properly attributed?
  • Does my reference list match my in-text citations?
  • Have I followed my university or journal's plagiarism policy?
  • Did I revise problematic matches?
  • Did I perform a final check after making major revisions?
  • Have I proofread the manuscript before submission?

Knowing how to check plagiarism before submission is an important part of responsible academic writing. A plagiarism checker can help you identify potentially problematic similarities, but the report should always be interpreted carefully.

The objective is not simply to achieve the lowest possible similarity score. Your goal should be to produce a manuscript that clearly distinguishes your original contribution from existing scholarship while giving appropriate credit to previous researchers.

Before submission, check the complete manuscript, examine individual matches, improve weak paraphrasing, verify citations, review possible self-plagiarism, and follow the specific requirements of your target journal or institution.

A careful plagiarism review can help you submit your research with greater confidence and demonstrate your commitment to academic integrity. For personalized guidance, you can book a consultation with our experts or explore our pricing plans.

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