Compare Quillbot and Diigo: Which Extension is the Best?

Quillbot is an AI-powered writing assistant designed to enhance your writing with features like paraphrasing, grammar checking, and summarizing. Ideal for productivity and improving writing quality.
Diigo is a handy tool for bookmarking, highlighting, and annotating web pages. It has many features, but its old design and limited highlight colors might make it less appealing.
Key Features
  • Paraphrasing Tool: Rewrites your sentences to improve clarity and style.
  • Grammar Checker: Identifies and corrects grammatical errors.
  • Summarizer: Condenses long texts into shorter summaries.
  • Citation Generator: Helps you create citations in various formats.
  • Plagiarism Checker: Ensures your content is original.
  • Highlighting: Works well and highlights are recreated on refresh.
  • Notes: You can add notes to your highlights.
  • Link Creation: Create links to your highlights, although this feature is not very reliable.
  • Sidebar Outliner: Simple design but requires time to understand.
  • Syncing: Highlights are synced across devices.
Our Rating
8.7
7.8
Total users
4,485,643
200,000
Total ratings
3,036
2,319
Average rating
4.6 ⭐
4.6 ⭐
Entry Level PriceFreeFree
Chrome
Chrome Web Store logo
4.7
4.88
2.9K+ ratings
4.0M+Users
Chrome Web Store logo
4.6
3.56
2.3K+ ratings
200.0K+Users
Edge
Microsoft Edge Store logo
4.5
4.47
104 ratings
485.6K+Users
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Firefox
-
-
Safari
-
-
Features
9.0

Paraphrasing Tool:
Quillbot's paraphrasing tool is one of its standout features. It offers multiple modes like Standard, Fluency, and Creative, allowing users to choose the level of rewriting they need. We found it particularly useful for avoiding plagiarism and improving sentence structure.

Grammar Checker:
The grammar checker is robust, catching errors that many basic spell checkers miss. However, it sometimes flagged correct sentences as incorrect, which can be a bit annoying.

Summarizer:
Quillbot's summarizer is effective for condensing long articles or papers. It provides concise summaries that capture the main points, making it a valuable tool for students and professionals alike.

8.5

Diigo offers basic features for a highlighter and bookmarking tool.

It works well and we were able to highlight most websites and they were recreated when revisiting them.

The highlighter popup makes it easy to highlight text offering 4 colors. It looks like this:

Highlighter Popup with four colors

We would have wished to have more color options.

Also, note-taking and the tagging functionality are working, but its design does not look appealing.

Notes Editor: Adding notes to your highlight

The dashboard where your highlights are stored works well and gives you an overview of all your highlights.

Diigo Dashboard
Performance
8.8

Quillbot performs well with small to medium-sized texts, but it can slow down when processing larger documents.

8.0

Diigo performs well in terms of highlighting and syncing across devices. The fact that highlights are always synchronized can cause some loading delays.

It's not as fast as other highlighters that use an offline-first approach, but it works reasonably well.

However, the unreliable link creation feature and the simple sidebar outliner design need improvement.

Design
9.0

User Interface:
Quillbot boasts a clean and intuitive interface. The layout is straightforward, making it easy for users to navigate through different features without any hassle.

Customization:
The tool offers various customization options, such as different paraphrasing modes and the ability to adjust the length of summaries. These features make it adaptable to different writing needs.

7.0

The design fulfills its functionality. The design of Diigo is outdated and could use a modern refresh.

The lack of a nice overview of all your highlights on the page itself means you have to open the dashboard on diigo.com instead.

The dashboard on diigo.com is okay, but other highlighters like Web Highlights have a much nicer user interface.

Value for Money
9.0

Free vs. Paid:
While the free version offers basic functionality, the premium plans unlock a wealth of features that significantly enhance the tool's utility.

Cost-Effectiveness:
Compared to its competitors, Quillbot is slightly cheaper than Grammarly but more expensive than LanguageTool. From our perspective, Quillbot doesn't offer more value than LanguageTool, so we believe it should be priced similarly. However, it currently offers significant discounts on their plans, which makes it a very good investment in your writing.

8.0

The free version of Diigo offers basic features and is fine for most users. The paid plans are reasonably priced and similar to other highlighters.

However, we think other highlighters offer more value for the same price.

Ease of Use
7.8

Quillbot's onboarding process is impressive, and the tool is easy to use right from the start. We quickly grasped most of its features. However, when compared to top competitors like Grammarly, it doesn't feel quite as natural or seamless to use.

7.8

Diigo is fairly easy to use, but the sidebar outliner takes some time to get used to.

You can't see all your highlights on the page itself, so you have to go to the dashboard on diigo.com.

We wish there was a sidebar to quickly access all our highlighted pages, like in the Web Highlights extension.

Security & Privacy
8.8

Data Handling:
Quillbot ensures that user data is encrypted and securely stored. However, like many AI tools, it does send data to its servers for processing, which may raise privacy concerns for some users.

Third-Party Services:
The tool uses third-party services for certain features, which could lead to data being processed outside of the EU. Users should be cautious when handling sensitive information.

7.5

Diigo takes reasonable steps to protect user data. However, since you need an account and your data is stored in their database, absolute protection can't be guaranteed.

We think a highlighter should work without needing to sign up, but this feature is missing in Diigo.

Conclusion

Quillbot is a flexible AI writing tool that does a great job with paraphrasing and grammar checking.

While it has a few minor downsides, like occasional mistakes and some privacy concerns, its overall performance and affordability make it a solid choice. In the end, choosing the best writing tool is also a matter of personal opinion. If you want to improve your writing and boost productivity, Quillbot is definitely worth a look.

However, it still cannot compete with Grammarly as the best writing tool in this category. In our eyes, Grammarly is worth the more expensive price.

Diigo is a handy tool for collecting stuff from the web, like bookmarks, highlights, and notes.


It’s a good deal with its premium plans, but the old-fashioned design and limited highlight colors might be a turn-off.


If you want something that looks nicer and offers more customization, check out alternatives like Web Highlights.

Our Recommendation

In our comparison between Quillbot and Diigo, Quillbot came out on top, scoring 8.7.

Quillbot is the most widely used, with over 4 million users and 3k+ reviews—and it also delivered the strongest performance in our tests. User reviews for Quillbot reflect our findings, while we rate Diigo lower than users do.

Notably, Diigo has the highest user rating in the Chrome Web Store at 4.60, which is even higher than our rating of 7.8.

There are some noticeable differences between these extensions, so it's worth considering your priorities and the details below.


  • Looking for the richest feature set? Quillbot stands out with a rating of 9. On the other hand, Diigo lags behind in this area with a rating of 8.5.
  • Need top performance? Quillbot stands out with a rating of 8.8. On the other hand, Diigo lags behind in this area with a rating of 8.
  • Design lovers, take note: Quillbot stands out with a rating of 9. On the other hand, Diigo lags behind in this area with a rating of 7.
  • Want to get the most for your money? Quillbot stands out with a rating of 9. On the other hand, Diigo lags behind in this area with a rating of 8.
  • Ease of use? It's a tie: Quillbot and Diigo. In the Ease of Use category, Quillbot has scored a decent 7.8. It is generally easy to use, but some aspects might be less intuitive.
  • With privacy and security becoming ever more important, Quillbot stands out with a rating of 8.8. On the other hand, Diigo lags behind in this area with a rating of 7.5.

If you want a quick recommendation, Quillbot is our top pick. But as always, the best choice depends on what matters most to you.