As someone who has worked in content strategy for almost 10 years, I know the importance of a solid content plan. Writing a detailed outline is the best way to tell your writers what to include in their blog posts.
But even for experienced content marketers, turning ideas into coherent, structured outlines can be a challenge. Back in 2021, this was a major bottleneck when scaling my content operations: I couldn’t write blog post outlines fast enough for my writers! My small business clients often have the same pain point. That can lead to either pausing content creation efforts or—worse—publishing low-quality blog posts with no strategy.
Now, four years later, there are dozens of AI outline generators. They help you turn keywords or topic ideas into logical, organized outlines in seconds, not hours. When done right, AI-generated outlines lay the foundation for effective, strategic content.
In this post, I’ll introduce you to a few outline generators I’ve tried, including SurferSEO, ChatGPT, and Google NotebookLM. I generated outlines and compared their quality, comprehensiveness, and presence of plagiarism. Read on for a review of AI outline generators from the perspective of a content marketing and SEO specialist.
Key takeaways:
- Well-structured outlines are part of a comprehensive content strategy
- AI tools can speed up your content creation process–but you need to make sure you’re using the right tools with the right input
- Structured outline from ChatGPT and Google NotebookLM may outperform both paid options and free AI outline generators from SEO tools
Table of Contents
Blog outline generators overview
Good content writing comes from strategic planning. An outline ensures the final draft encompasses the required topics and information. While a comprehensive outline doesn’t guarantee a high-quality final product, it always helps.
What is an outline generator?
An outline generator is an AI-powered tool that helps you create a structured content framework for various content types, such as blog posts, landing pages, research papers, books, speeches, or essays. This article focuses on blog outlines.
Why are structured blog outlines important?
Both people and search engines want to find useful information on a page. A solid content outline is a clear structure to make sure you hit all the main points before you ever start writing.
Structured blog outlines are essential for working with different writers. It’s how a content manager can ensure the logical progression, key points, and consistent structure across many writers and writing styles.
In my experience, posts that start with good outlines are ready to publish about twice as quickly as drafts that come from a keyword alone. Meanwhile, the content quality improves and the websites rank for more keyword variations.
The 5 AI tools I tested to write blog post outlines
SurferSEO: Paid content outline generator
I used SurferSEO first as a content writer and then as the head of marketing operations for a pre-seed startup. It has a learning curve, but it’s user-friendly for both SEO copywriters and content editors. SurferSEO does a great job of solving the blank page issue by using top-ranking pages to generate an outline based on your target keyword.
SurferSEO: Free AI outline generator tool
I’ve never used this free tool before. The prompting window was shorter than any of the other options (200 characters), so I was only able to input my keyword target with no reference links.
ChatGPT: Free plan, logged out
I used ChatGPT in an incognito browser window to generate the blog post outline. I didn’t want any of my previous content work to influence the outline. To make this as similar as possible to the other tools, I only offered a very basic prompt requesting an outline for a blog post with a specific keyword and set of links.
Ahrefs: Free outline builder tool
I have used Ahrefs for competitive research and backlink building for years, but this was the first time I tried the free outline generator. I found it straightforward and fast. The outline was solid yet minimal, with only section headings and no bullet points or citations.
Google NotebookLM: Free limited language model
Google’s NotebookLM tool works a bit differently. I set up a new notebook with the most relevant pages from the first two pages of Google and my custom template as sources. I used this tool to write two outlines: with and without my template. Both outlines were detailed, included sources for nearly every line, and suggested sections and topics to include.
My evaluation process for the generated blog post outlines
In this test, I used the same keyword and the same selected links from the top 20 search results. I used the five tools introduced above for a total of seven tests. I used NotebookLM and SurferSEO twice: once using my custom-built content brief template, and once without. In the spirit of transparency, here is a view-only version of the template I used.
To compare the results, I used SurferSEO to check for plagiarism, as I do whenever I use AI-generated content.
I used the Search Quality Evaluator GPT, trained by Caitlin Hathaway, to rate each outline according to Google’s 36-page Search Quality Evaluator Guidelines. The GPT gives a “page quality” and a “needs met” score.
- Page quality has to do with the content’s coverage of a topic and content structure on a 9-point scale from Lowest to Highest
- Needs met rating is based on how well the content satisfies the search intent for a given keyword on a 5-point scale from “Fails to Meet” to “Fully Meets”
Experiment challenges and limitations
I only tested one keyword across these tools, so it’s possible the outlines based on other keywords would show different results. I wanted to test each tool based on the same subject, but this is in no way a definitive judegment.
I wasn’t able to use the same links for each outline as I planned. One tool didn’t allow any links at all. One link failed to upload to my NotebookLM because the page required a sign-in to Medium. I can’t say for sure if the other options used that link or silently failed.
ChatGPT cited sources outside of the links I identified, offering advice from Reddit several times. The advice was sound, but I asked for an outline based on my specified links, and ChatGPT failed to deliver.
In the future, I’d want to test this with more keywords and more tools. Grammarly, Frase, Jasper, Copy.ai, Writesonic, and other SEO tools have outline options I didn’t test for this article.
How do content outline tools compare?
I wanted to find the best option for detailed outlines to support SEO-friendly, high-quality content when expanded into a polished draft. Ideally, I also wanted the blog outline generator to be completely free.
Examples of AI-generated blog post outlines
Outline comparison chart
| Tool | Page Quality Rating | Needs Met Rating | Plagiarism Detected? |
|---|---|---|---|
| Google NotebookLM (with template) | High+ | Highly Meets | No |
| Google NotebookLM (no template) | High+ | Highly Meets | No |
| ChatGPT | High | Highly Meets | No |
| Ahrefs AI Outline Generator (free) | High | Highly Meets | No |
| SurferSEO (paid with template) | High | Highly Meets | No |
| SurferSEO (paid, no template) | Medium+ | Moderately Meets | Yes; 15% |
| SurferSEO (free) | Medium+ | Moderately Meets | No |
What I learned from testing 5 AI outline generators
My NotebookLM-generated outlines scored best, earning “High+” page quality ratings and “highly meets” needs met ratings. The ChatGPT and SurferSEO outputs also earned “highly meets” ratings, but lower page quality scores with a “high” instead of “highest.”
I expected the free SurferSEO tool to have the lowest rating and it did, garnering only a “medium+” page quality score and “moderately meets” for needs met rating.
Unexpectedly, it tied with the paid version of SurferSEO’s outline. I’ve used SurferSEO for several projects, so I know the tool is much more than an outline generator, but this experiment exposed a serious limitation. Without a template, SurferSEO’s suggested outline “moderately meets” Google’s page quality guidelines and earns a “medium+” for page quality. By Surfer’s own measurement, it plagiarized 15% of its content. None of the other outlines flagged any plagiarized content.
The Google NotebookLM outline scored the highest and was the best at attributing stats and quotes to other articles. This is the outline tool I will recommend to my clients.
AI outline generators speed up content creation, but strategy still matters
To sum up, my evaluation revealed that all the AI tools I tested can support your content operations, and free options can outperform paid alternatives. SurferSEO is still a solid choice for an AI writing tool, especially if your writers are not subject matter experts; however, I found that it requires either a detailed outline template or an outline from another source to reach a high page quality score.
Using structured outlines consistently delivers measurable content marketing results. When done right, AI-generated outlines lay the foundation for effective, high-quality content that supports your business objectives.
I plan to build my NotebookLM outline generator out into a repeatable, scalable process for lean marketing teams. If you want to see that update, please follow Edit Ever After on LinkedIn.
FAQs about online generators
Why use AI technology for content planning?
Free outline generators and other free AI tools speed up the content writing process without costing anything. This is ideal for small businesses and other small teams who need all the useful free help they can get.
Can AI outline generators replace human content strategists?
No. Content strategists do more than write content outlines; content strategy involves understanding your audience, competitive positioning, and business goals. It requires knowing when to pivot based on market changes and when to double down on the content that’s driving leads. AI can’t make those judgment calls. So while AI outline generators are useful tools for speeding up content creation, they can’t yet replace humans in the content planning process.
Should I use a template with AI outline generators?
Yes. I tested my outline template with two tools, and SurferSEO showed an improved page quality and needs met score, while NotebookLM scored the same either way.
However, a template helps you produce consistent content in addition to improving search quality rating. Without a template, your drafts may or may not include FAQs, conclusions, or takeaways. A template will ensure the elements you want every time.
Does Surfer’s outline builder only suggest article titles?
No, Surfer SEO’s outline generator includes several on-page SEO elements in addition to article titles. Surfer suggests section headings, keywords and topics to cover, meta descriptions, and internal linking opportunities.
