Should I check my paper for plagiarism before submitting it to my instructor?

If you’ve correctly cited all the sources you used, then you do not need to use a plagiarism checker before submitting your paper to your instructor. However, it is very easy to commit plagiarism accidentally, even if you’ve been very careful. To ensure that you didn’t forget to cite anything, you should use a plagiarism checker yourself.

A plagiarism checker works by using advanced database software to scan for matches between your text and existing texts.

To help you decide which checker to use, we conducted in-depth research comparing popular plagiarism checkers to find out which one is best.

Best plagiarism checker comparison

How Do Plagiarism Checkers Work?

Frequently asked questions: Plagiarism Checker

Can I buy a monthly subscription for the Scribbr Plagiarism Checker?: At the moment we do not offer a monthly subscription for the Scribbr Plagiarism Checker. Plagiarism checks can be bought separately — prices depend on the size of your document.

Small document (up to 7,499 words) £13.95

Normal document (7,500-49,999 words) £22.95

Large document (50,000+ words) £31.95
Why are similarities marked in different colours?: Similarities in your document are highlighted for quick and easy review. Each colour corresponds to a source in your Sources Overview at the right side of your report.
I don’t recognize a source found by the plagiarism checker. What now?: Information can often be found in more than one place. For this reason, other sources citing the same information you used can come up in your Sources Overview.

The important thing is to make sure you’ve cited the source of the material. Try to find the original source, but if you can’t find it, it’s best to cite the source where you found the information.
What does a “high” or “moderate” risk of plagiarism mean?: Scribbr’s free plagiarism checker estimates the risk of plagiarism by calculating the percentage of text in your document that’s similar to other sources.

A moderate or high risk of plagiarism means that the plagiarism software detected several similarities worth reviewing.

Note that similarities are not necessarily plagiarism. You will need to decide on your own whether your text needs revision or citation.
What is the difference between the free and premium report?: The free report tells you if your text contains potential plagiarism and other writing issues. The premium report gives you the resources you need to review issues in detail and resolve them.

Free report Premium report (from $19.95)

Plagiarism Checker

Plagiarism risk assessment

Top matching sources

Grammar Checker

Number of writing issues

Plagiarism Checker

Precise similarity percentage

Complete list of matching sources

Document view to quickly review similarities

Side-by-side comparison with the original text

Upload private documents

Grammar Checker

Downloadable Word document with all your writing issues corrected using Track Changes

AI Detector

Precise AI writing percentage
Can you use the Scribbr Plagiarism Checker for free?: Yes, Scribbr offers a limited free version of its plagiarism checker. It uses the industry-leading plagiarism detection technology and has access to most content databases.

Run a free plagiarism check
What is an acceptable percentage of plagiarism?: Your work should not contain any plagiarism. Even if your score is 1%, you will need to review each similarity and decide whether it’s necessary to revise your work.

But contrary to popular belief, plagiarism checkers work by detecting not plagiarism, but similarities. Not all similarities found by the Scribbr Plagiarism Checker constitute plagiarism. Our check sometimes flags the following:

Properly cited quotes

In-text citations or your reference list

Commonly used phrases

What should I do with a found similarity?
How accurate is Scribbr’s plagiarism checker?: Extensive testing proves that Scribbr’s plagiarism checker is one of the most accurate plagiarism checkers on the market in 2024.

The software detects everything from exact word matches to synonym swapping. It also has access to a full range of source types, including open- and restricted-access journal articles, theses and dissertations, websites, PDFs, and news articles.
What languages are supported by the plagiarism checker?: Scribbr’s plagiarism checker offers complete support for 20 languages, including English, Spanish, German, Arabic, and Dutch. The add-on AI Detector is available for English, Spanish, German, French and Dutch texts.

The complete list of supported languages:

Arabic

Bosnian

Croatian

Czech

Danish

Dutch

English

Finnish

French

German

Greek

Italian

Norwegian

Polish

Portuguese

Russian

Serbian

Spanish

Swedish

Turkish
What plagiarism and AI detection software does Scribbr use?: Scribbr uses advanced plagiarism detection technology similar to the software used by most universities and publishers in the UK, ensuring you receive the same or very similar results.

The add-on AI detector is powered by Scribbr’s proprietary software and is capable of detecting texts generated by ChatGPT, Perplexity and other generative AI tools with high accuracy.
To which databases will my document be compared?: Your document will be compared to the world’s largest and fastest-growing content database, containing over:

99.3 billion current and historical webpages.

8 million publications from more than 1,700 publishers such as Springer, IEEE, Elsevier, Wiley-Blackwell, and Taylor & Francis.
Can other plagiarism checkers see my submissions to Scribbr?: Your writing stays private. Your submissions to Scribbr are not published in any public database, so no other plagiarism checker (including those used by universities) will see them.
Will Scribbr give the same result as my university’s plagiarism checker?: Scribbr uses similar plagiarism software to most universities in the UK, providing the same or very similar results.

However, universities may check your work against private student paper databases, which Scribbr can’t access, possibly leading to small differences.

To help, Scribbr offers a free Self-Plagiarism Checker add-on, allowing you to manually upload your source documents to ensure you haven’t accidentally plagiarized.

Small document (up to 7,499 words)	£13.95
Normal document (7,500-49,999 words)	£22.95
Large document (50,000+ words)	£31.95

Free report	Premium report (from $19.95)
Plagiarism Checker Plagiarism risk assessment Top matching sources Grammar Checker Number of writing issues	Plagiarism Checker Precise similarity percentage Complete list of matching sources Document view to quickly review similarities Side-by-side comparison with the original text Upload private documents Grammar Checker Downloadable Word document with all your writing issues corrected using Track Changes AI Detector Precise AI writing percentage

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Want to contact us directly? No problem. We are always here for you.

Frequently asked questions

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How can I contact Scribbr?: Our support team is here to help you daily via chat, WhatsApp, email, or phone between 9:00 a.m. to 11:00 p.m. CET.
Can I choose between the 6th and 7th editions of APA Style?: Our APA experts default to APA 7 for editing and formatting. For the Citation Editing Service you are able to choose between APA 6 and 7.
Can I get a sample edit?: Yes, if your document is longer than 20,000 words, you will get a sample of approximately 2,000 words. This sample edit gives you a first impression of the editor’s editing style and a chance to ask questions and give feedback.

How does the sample edit work?

You will receive the sample edit within 24 hours after placing your order. You then have 24 hours to let us know if you’re happy with the sample or if there’s something you would like the editor to do differently.

Read more about how the sample edit works
Can I upload my document in sections?: Yes, you can upload your document in sections.

We try our best to ensure that the same editor checks all the different sections of your document. When you upload a new file, our system recognizes you as a returning customer, and we immediately contact the editor who helped you before.

However, we cannot guarantee that the same editor will be available. Your chances are higher if

You send us your text as soon as possible and

You can be flexible about the deadline.

Please note that the shorter your deadline is, the lower the chance that your previous editor is not available.

If your previous editor isn’t available, then we will inform you immediately and look for another qualified editor. Fear not! Every Scribbr editor follows the Scribbr Improvement Model and will deliver high-quality work.
Can I have my document edited during weekends and holidays?: Yes, our editors also work during the weekends and holidays.

Because we have many editors available, we can check your document 24 hours per day and 7 days per week, all year round.

If you choose a 72 hour deadline and upload your document on a Thursday evening, you’ll have your thesis back by Sunday evening!
English is not my first language. Can you fix all my mistakes?: Yes! Our editors are all native speakers, and they have lots of experience editing texts written by ESL students. They will make sure your grammar is perfect and point out any sentences that are difficult to understand. They’ll also notice your most common mistakes, and give you personal feedback to improve your writing in English.
What types of editing does Scribbr offer?: Every Scribbr order comes with our award-winning Proofreading & Editing service, which combines two important stages of the revision process.

For a more comprehensive edit, you can add a Structure Check or Clarity Check to your order. With these building blocks, you can customize the kind of feedback you receive.

You might be familiar with a different set of editing terms. To help you understand what you can expect at Scribbr, we created this table:

Types of editing Available at Scribbr?

Proofreading
Correction of superficial mistakes, such as typos, misspellings, punctuation errors and consistency errors. Yes!
This is the “proofreading” in Scribbr’s standard service. It can only be selected in combination with editing.

Copy editing
Focus on grammar, syntax, style, tone and the conventions of the field. The editor also considers the internal logic of the text and flags any obvious contradictions. Yes!
This is the “editing” in Scribbr’s standard service. It can only be selected in combination with proofreading.

Line editing
Focus on language, style, concision and choices. The editor helps you strengthen your story, polish your sentences and ensure that your use of language drives home your ideas. Yes!
Select the Structure Check and Clarity Check to receive a comprehensive edit equivalent to a line edit.

Developmental editing (i.e. content editing, substantive editing)
This is the first step of the editing process and applies to very early drafts. The editor helps you structure your ideas, decide what story to tell and find direction for your writing. No.
This kind of editing involves heavy rewriting and restructuring. Our editors cannot help with this.

View an example
Is the editor an expert in my field of study?: When you place an order, you can specify your field of study and we’ll match you with an editor who has familiarity with this area.

However, our editors are language specialists, not academic experts in your field. Your editor’s job is not to comment on the content of your dissertation, but to improve your language and help you express your ideas as clearly and fluently as possible.

This means that your editor will understand your text well enough to give feedback on its clarity, logic and structure, but not on the accuracy or originality of its content.

Good academic writing should be understandable to a non-expert reader, and we believe that academic editing is a discipline in itself. The research, ideas and arguments are all yours – we’re here to make sure they shine!
How do I receive my document when the editor has finished proofreading?: After your document has been edited, you will receive an email with a link to download the document.

The editor has made changes to your document using ‘Track Changes’ in Word. This means that you only have to accept or ignore the changes that are made in the text one by one.

It is also possible to accept all changes at once. However, we strongly advise you not to do so for the following reasons:

You can learn a lot by looking at the mistakes you made.

The editors don’t only change the text – they also place comments when sentences or sometimes even entire paragraphs are unclear. You should read through these comments and take into account your editor’s tips and suggestions.

With a final read-through, you can make sure you’re 100% happy with your text before you submit!
I have a tight deadline. Can you edit my document in time?: You choose the turnaround time when ordering. We can return your dissertation within 24 hours, 3 days or 1 week. These timescales include weekends and holidays. As soon as you’ve paid, the deadline is set, and we guarantee to meet it! We’ll notify you by text and email when your editor has completed the job.

Very large orders might not be possible to complete in 24 hours. On average, our editors can complete around 13,000 words in a day while maintaining our high quality standards. If your order is longer than this and urgent, contact us to discuss possibilities.

Always leave yourself enough time to check through the document and accept the changes before your submission deadline.
What type of documents does Scribbr proofread?: Scribbr is specialised in editing study related documents. We check:

PhD Theses

Graduation projects

Dissertations

Essays

Admissions essays

College essays

Application essays

Personal statements

Reports

Process reports

Reflections

Internship reports

Academic papers

Interviews

Proposals

Research proposals

Prospectuses

Calculate the costs
How fast can Scribbr proofread my document?: The fastest turnaround time is 24 hours.

You can upload your document at any time and choose between four deadlines:

Same day delivery

3 hours

6 hours

12 hours

24 hours

3 days

7 days
What is Scribbr’s 100% happiness guarantee?: At Scribbr, we promise to make every customer 100% happy with the service we offer. Our philosophy: Your complaint is always justified – no denial, no doubts.

Our customer support team is here to find the solution that helps you the most, whether that’s a free new edit or a refund for the service.
Can I choose between American, British and Australian English?: Yes, in the order process you can indicate your preference for American, British, or Australian English.

If you don’t choose one, your editor will follow the style of English you currently use. If your editor has any questions about this, we will contact you.

Types of editing	Available at Scribbr?
Proofreading Correction of superficial mistakes, such as typos, misspellings, punctuation errors and consistency errors.	Yes! This is the “proofreading” in Scribbr’s standard service. It can only be selected in combination with editing.
Copy editing Focus on grammar, syntax, style, tone and the conventions of the field. The editor also considers the internal logic of the text and flags any obvious contradictions.	Yes! This is the “editing” in Scribbr’s standard service. It can only be selected in combination with proofreading.
Line editing Focus on language, style, concision and choices. The editor helps you strengthen your story, polish your sentences and ensure that your use of language drives home your ideas.	Yes! Select the Structure Check and Clarity Check to receive a comprehensive edit equivalent to a line edit.
Developmental editing (i.e. content editing, substantive editing) This is the first step of the editing process and applies to very early drafts. The editor helps you structure your ideas, decide what story to tell and find direction for your writing.	No. This kind of editing involves heavy rewriting and restructuring. Our editors cannot help with this.

Frequently asked questions

Should I check my paper for plagiarism before submitting it to my instructor?

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Frequently asked questions: Plagiarism Checker

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