Content
Optimiser
A free content optimiser that benchmarks your draft against the top-ranking pages on the SERP. Paste your blog post and the competitors, get an instant optimisation score across 8 quality checks, a 1-4 word keyword density gap analysis, and a ready-to-use ChatGPT prompt. No login. No fluff.
A free content optimiser analyses your draft against the top-ranking pages on the search engine results pages for your target keyword. It identifies which key phrases and related keywords the SERP is leaning on, flags gaps in your keyword density, scores your readability, and tells you how close your word count is to the ranking median. SEO content optimisation tools surface the statistical patterns Google associates with a topic. Treat the results as a brief, not a finished article.
Everything runs in your browser. Nothing is sent to a server.
The same entity coverage that earns SERP rankings also wins citations from AI engines. Large language models behind ChatGPT, Perplexity, Claude, and Google AI Overviews are trained on the same web Google indexes. If your draft now covers the topical entities the ranking pages share, you have moved closer to being citation-worthy by answer engines too.
Density alone is not enough for AEO. Pair this with schema markup, factual anchors (specific numbers and dates), clear definitions in opening paragraphs, and an AEO readiness check to round out the picture.
- Aim for an optimisation score above 80 before publishing. Below 60 means too many SERP phrases are missing from your draft.
- Match the SERP median word count. Articles dramatically shorter than the top-ranking pages rarely break in.
- Treat any phrase appearing in 3 or more competitors as a topical signal worth respecting — these are the entities Google sees regularly across the top of the SERP.
- Readability between 60 and 70 (Flesch) suits most blog post content. Match the register of the SERP, not an arbitrary target.
- Use the GPT prompt to draft the missing paragraphs, then edit by hand. Never publish the LLM output raw.
- Density is a diagnostic, not a rulebook. Add phrases in natural sentences. Keyword stuffing will harm CTR and trip spam signals.
- Cross-reference low-CTR pages from Google Search Console — those are where optimising existing content delivers the fastest organic traffic lift.
What is a Content Optimiser?
A content optimiser is one of a class of SEO content optimisation tools that compares your draft article against the pages currently ranking on google search for your primary keyword. It surfaces the relevant keywords the ranking pages are using, your usage versus the SERP average, and the gaps. The output is a content brief, not a finished article, that tells you which entities and key phrases to weave into your content before publishing. Modern content optimisation tools often combine keyword research, density analysis, and natural language processing to do this at speed.
A keyword density tool sits inside most content optimisers and counts how often a particular keyword appears as a percentage of total words. Modern SEO does not treat density as a direct ranking signal, but the ranking pages tend to cluster around similar density ranges for the most important phrases. That clustering is a useful proxy for topical coverage, which search engines do care about. The best content optimisation tools combine this with keyword research, search intent matching, and competitor analysis to build a complete picture.
"A fantastic content strategy partner who has helped Originality continue to grow into one of the industry-leading AI detection software tools, with excellent exposure across Google, LLMs, and Socials."
What Does This Content Optimiser Analyse?
This free tool runs 8 checks every time you paste your draft and the SERP. Here is what each one looks at and why it matters for ranking and reader engagement. Need help fixing a wider on-page SEO issue across the whole site? See GWContent's on-page SEO service.
Primary keyword presence
Your primary keyword (also called the target keyword or focus keyword) should appear naturally in the body, ideally within the first 100 words and again in the closing paragraphs. The tool checks whether the keyword appears at all and whether the density sits within the ±0.25% band of the SERP average. Front-loading the target keyword helps search rankings and reader scanability in equal measure.
Topic coverage
The percentage of the top phrases used by the ranking pages that you also use within the target band. High coverage means you have covered the same topical ground as the SERP. Low coverage means you are missing related keywords and entities that search engines associate with the topic via natural language processing.
Word count vs SERP median
The ideal word count is the median of the competitor articles you pasted. Hit it or beat it. Articles dramatically shorter than the SERP rarely rank, and long form content beyond the median rarely justifies the length without genuine depth. Match the SERP, then earn the right to extend.
Readability (Flesch)
Flesch Reading Ease scores your sentence length and syllable complexity. 60-70 is the sweet spot for most blog post content. Below 50 reads like a legal document. The tool flags any score outside the readable range for your target audience. Readability feeds into content score and content grade systems used across most SEO tools.
Phrase variance
How tightly your phrase density tracks the SERP average across the keyword data. Tight variance means you are inside the band on most phrases. Wide variance means you are over-using some phrases and under-using others, which signals incomplete topical coverage. This is where content optimization tools earn their keep.
2-word phrase coverage
Bigrams (2-word key phrases) carry more semantic weight than single words. The tool checks whether you are using the same multi-word entities the ranking pages are using. Missing bigrams is the most common reason a draft scores below 60, and is a core focus of any on-page optimisation pass.
Long-tail phrase coverage
3 and 4-word phrases reveal the specific framings the SERP uses, mapping closely to search intent. If 4 competitors all say "the right content optimisation tool" and your draft never uses that framing, you are missing a query variant. The tool surfaces these as keyword suggestions for inclusion. For volume and keyword difficulty data on specific phrases, pair this with a dedicated keyword research tool.
Competitor depth
How many competitors you analysed in your SERP analysis. 3 is the minimum for a useful signal. 5 is the sweet spot. 10 gives the most robust competitive analysis but takes longer to set up. The tool weighs the confidence of its score based on this number.
Common Content Optimisation Mistakes (And How to Fix Them)
Most under-performing drafts make the same handful of errors. These are the ones that show up most often in content audits — each one costs ranking, traffic, or both.
Google ranks topical authority, not keyword frequency. A page that covers the full entity set and answers the target audience's underlying questions looks more authoritative than one that hammers a single keyword.
Keyword stuffing harms readability, lowers time on page, and trips the spam signals search engines have been trained on for over a decade. It hurts both SEO performance and search rankings.
Google reads length as a proxy for depth. Thin pages rarely earn ranking on competitive head terms regardless of how well-written they are. Aim for comprehensive content that matches or beats the ideal word count of the ranking pages.
Padding inflates word count and lowers engagement metrics. Length only helps when it earns its place. Across content marketing and digital marketing as a whole, dwell time and organic traffic conversion matter more than raw word count.
Search intent mismatch is the silent killer of optimisation work. A perfect content score against the wrong SERP gets you no closer to the right search results.
A 95 SEO score with poor writing converts worse than an 80 score with strong writing. Density is a coverage signal, not a quality content signal. High-quality content beats high-scoring content every time.
Keyword Density: A Complete Guide
Keyword density is the percentage a particular keyword or phrase represents of your total word count. It is one of the most misunderstood metrics in SEO and across content optimisation tools generally. There is no official target — Google has confirmed it does not use a fixed density threshold. The useful signal is comparative: how does your density compare to the pages that already rank? Use this alongside Google Search Console data to find the queries that are surfacing your pages, then optimise the highest-impressions, lowest-CTR ones first.
If you have dozens of pages losing rankings, density is unlikely to be the sole cause. A content refresh programme identifies decay across the entire library and prioritises rewrites by traffic impact.
How to Use This Content Optimiser
The tool runs entirely in your browser. You paste, you analyse, you act. Five steps from cold draft to ready-to-publish.
Pick one primary keyword
One phrase. Not a list. Not a theme. The primary keyword (sometimes called focus keyword or target keyword) you want this page to rank for above all others. Enter it in the top field.
Paste your full draft
The complete article body. Strip out nav, footer, and boilerplate so the density analysis stays honest. The live snapshot shows word count, sentences, and a running Flesch readability score as you type. If you draft in Google Docs, paste the plain text, not the formatted block.
Pull the SERP
Search your keyword in an incognito window. Open the top 3 to 10 results. Use Reader mode to extract just the body content. Paste each into a competitor field.
Hit analyse
The tool returns your optimisation score, word count vs target, readability, eight pass/fail checks, and a four-tab density gap analysis covering 1, 2, 3 and 4-word phrases. The actionable recommendations point to specific ranking improvements you can make before publishing.
Close the gap
Copy the ChatGPT prompt to draft the missing paragraphs (it works as a quick SEO writing assistant), or rewrite by hand. Export the CSV if you want a record for your content workflow. Re-run the analysis after your edits to confirm the score has moved.
Density Is One Signal Among Many
Keyword density gap analysis tells you whether your draft covers the same topical ground as the SERP. It does not tell you whether your domain has the authority to rank in the first place. A 95-score article on a low-authority site will lose to a 60-score article from an established publisher with strong E-E-A-T signals, comprehensive content, and a dense internal link graph. No single content optimiser, AI powered SEO tool, or SEO writing assistant gets around that. Treat this tool as one input across your content workflow, not the deliverable.
Other factors that move the needle, and where to address each:
llms.txt file declaring your content to LLM crawlers, entity clarity (each H2 answering one query directly), and answer-shaped opening paragraphs that define the topic before any narrative kicks in. The optimisation score tells you density is right. None of those signals are measured here.If your content keeps scoring well on tools like this one but still does not rank, the bottleneck is almost always upstream of the draft. Authority, internal linking suggestions worth following, schema coverage, meta titles, meta descriptions, internal links, and entity recognition do the heavy lifting on SEO performance and search engine rankings. Sound on page SEO sits underneath everything. Density gap analysis polishes the last 20%. For the full picture across the content lifecycle — strategy, content creation, optimisation, distribution — including how to optimize content already published — engage on a proper SEO consulting brief.
This tool was built by Graeme Whiles, an SEO and AEO strategist with over a decade of content marketing experience. Graeme has managed organic growth strategies for brands including Originality.ai (organic traffic +325%), Connecteam (+62.6%), 6sense, Practice Better, and Peppr — independently through GWContent. The checks in this tool are based on published Google guidance, established on-page SEO best practice, and direct SERP testing across hundreds of client pages.
This content optimiser is best suited for SEOs, content managers, and writers who want a fast, free way to benchmark a single draft against the SERP before publishing. If you have a large site with hundreds of articles to audit at once, you will need either Surfer SEO, MarketMuse, or a managed service. For a deeper engagement on content strategy or SEO, see GWContent's AI Visibility Audit or get in touch directly.
This Tool vs Surfer SEO, MarketMuse and Clearscope
Honest read across the main paid alternatives. The paid tools earn their fee if you optimise content weekly across a team. This tool earns its place as a free sanity check before you hit publish, and a way to test whether density gap analysis is even part of your workflow before you commit to a subscription.
| Feature | GWContent Optimiser | Surfer SEO | MarketMuse | Clearscope |
|---|---|---|---|---|
| Price | Free | From $89/month | Enterprise (POA) | From $189/month |
| Signup required | No | Yes | Yes | Yes |
| SERP scraping | Manual paste | Automatic | Automatic | Automatic |
| NLP depth | Statistical n-gram | Deep | Deepest | Deep |
| 1-4 word density analysis | Yes | Yes | Yes | Yes |
| Content briefs | No | Yes | Yes | Yes |
| Google Docs integration | No | Yes | Yes | Limited |
| GPT prompt export | Yes | No | No | No |
| AEO signal coverage | Partial | No | No | No |
| Runs in browser, private | Yes | No | No | No |
| Best for | Quick sanity check before publish | Weekly content workflow | Enterprise content teams | Agencies and publishers |
Pricing as of May 2026. Check each vendor for current rates. AEO signal coverage refers to whether the tool explicitly addresses answer engine optimisation factors beyond density.
Frequently Asked Questions
Not directly, no. Google stopped using keyword density as a primary ranking signal years ago. What its natural language processing does use is topical coverage and entity recognition, which density indirectly reflects. If the top 10 ranking pages all use a particular keyword 8 to 12 times and yours uses it once, that is a topical coverage gap. Density is the proxy. Use the tool to spot the gap, then close it with prose that earns its place.
Three is the floor. Five is the sweet spot. Ten gets you a robust average but takes longer to set up. For low search volume or low keyword difficulty terms, three top-ranking pages is enough. For a competitive head term with high search volume, push to eight or ten. The tool factors competitor count into the confidence of the optimisation score.
Browsers block JavaScript from reading the contents of other domains. That is a security feature, not a bug. To fetch competitor URLs server-side I would need a backend that costs money to run, which would mean either a signup wall or a paid tier. I would rather you paste the text and keep the tool free and private. Use Reader mode in your browser to extract clean body copy in a couple of clicks.
No. Everything runs locally in your browser. No analytics on the tool inputs, no server calls, nothing logged. Refresh the page and the data is gone. Your draft and competitor copy never leave your device.
Surfer SEO fetches the SERP for you, runs deeper NLP, generates content briefs, integrates with Google Docs, offers internal linking suggestions and a built-in blog post generator, and packages all the features into a polished, user-friendly interface. It is a properly resourced product with a team behind it. Across SEO optimisation generally, the best content optimisation tools at the paid end of the market — Surfer, MarketMuse, Clearscope — earn their fee on volume. This tool runs the core density gap analysis for free in your browser, no signup, no free plan trial. If you optimise content weekly across a content team, paid SEO tools pay back. If you optimise occasionally and want a sanity check before publishing, this is enough.
Yes. The prompt is model-agnostic. It lists the phrases the SERP uses that your draft is missing and asks the assistant to create content — three paragraphs that fold those phrases in naturally. Works in ChatGPT, Claude, Gemini, or any reasonable LLM. Always edit the output by hand before publishing.
The SEO score is the percentage of the top SERP phrases that your draft uses within the ±0.25% density band, weighted across 1-word and 2-word phrases. It is comparable to the content score or content grade used across most other tools in the category. 80+ means you are inside the band on most phrases and your draft is reasonably search optimized. Below 60 means you are missing too many of the entities the ranking pages are signalling. Treat 80 as the publish-ready threshold, not 100.
Indirectly, yes. AI Overviews, ChatGPT citations, Perplexity answers, and Claude responses are generated from training data that includes the same SERPs Google ranks. When your content covers the entities and phrases the ranking pages share, you become statistically more likely to be cited by the LLMs behind these answer engines. Density is one input, not the deliverable. To improve AEO directly, also work on schema markup, factual anchors, and answer-shaped opening paragraphs.
Substantially overlapping, but not identical. Classic Google search ranks pages on a SERP. AI engines extract claims, citations, and answer fragments from pages and re-synthesise them. The signals that matter for both include topical authority, entity coverage, factual specificity, schema markup, and E-E-A-T. AI engines pay extra attention to direct definitions, structured comparisons, and verifiable statistics — content that can be cited cleanly. Classic search pays more attention to backlinks and click signals.
Same direction, different emphasis. The base layer — topical authority, entity coverage, clear writing — works for both. To increase ChatGPT citation specifically, lead each section with a direct definition or factual statement, add concrete numbers and dates that LLMs can quote verbatim, use FAQ-style structures with clear question-answer pairs, and mark up your page with FAQPage and HowTo schema. The density gap analysis in this tool covers the entity layer. The structural and factual layers need separate attention.
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