SEO tools by job: the categories, free and paid

An SEO tool is software that measures, checks or speeds up one job in search engine optimization (SEO). The jobs are finding keywords, crawling your site, checking pages, tracking rankings, reviewing links and measuring results. No single tool covers all six well, so match each tool to a job. This article groups tools by job, names the free ones you can start with, and lists what to check before you rely on a tool's numbers.

The article is an overview, not a ranking. It cites vendor documentation for every feature and limit. Vendors change both, so read the linked page before you decide. Facts about limits are current as of October 2026.

What counts as an SEO tool

Google's SEO starter guide defines SEO as "helping search engines understand your content." It also says that Google finds most sites on its own by crawling the web. So the work has two parts: make the site easy to understand, and check that the engine understood it. A tool helps with one or both parts. Keep that split in mind as you read the categories below, because it tells you whether a tool changes your site or only reports on it.

That definition sorts tools into two groups:

• Tools that act on your site. A plugin that writes a meta description field, a generator that makes an Extensible Markup Language (XML) sitemap, or a publishing tool that posts an article.
• Tools that read data. A crawler that fetches your pages, a report that shows search queries, or a service that records where a page ranks.

Most products mix both. A WordPress plugin may write your sitemap and score your draft. A suite may crawl your site and track your rankings. The useful question is not "which tool is an SEO tool". It is "which job does this tool do, and how does it get its data".

The six jobs

This article uses six jobs. They follow the order of the work: you find a topic, publish a page, check that the engine reads it, and measure what happens.

Job	The question it answers	Where the data comes from
Keyword research	What do people search for, and how often?	An engine's own ad data, or a vendor's estimates
Crawling and audit	Can a crawler read every page, and what breaks?	Your own site, fetched by the tool
On-page checks	Does this page follow good practice?	The page you are editing
Rank tracking	Where does each page appear for each query?	Search result pages, collected by a tool
Links	Who links to the site, and who linked before?	A search engine's report or a vendor's own crawl
Measurement	Did search send visitors, and what did they do?	Search Console and an analytics service

The rest of the article takes each job in turn. Free tools from the search engines come first, because they hold the only first-party data.

Start with the official tools

Search engines publish tools that show how they see your site. Their data is first-party. It comes from the engine's own systems, not from a vendor's estimate. Set these up before you add anything else.

Google Search Console

Search Console is a free Google service for monitoring and troubleshooting your site's presence in Google Search. Google says you do not need to sign up to appear in results, but the tool shows how Google sees your site. Its help page lists these uses:

• Check that Google can find and crawl your site.
• Fix indexing problems and ask for new or updated content to be crawled again.
• View search traffic data, including impressions, queries and click-through rates.
• Receive alerts about indexing, spam and other issues.
• See which sites link to yours.

Two reports matter most for day-to-day work.

The Performance report shows four metrics. Clicks count visits from Google Search to your site. Impressions count how often your site appeared in results. Click-through rate (CTR) is clicks divided by impressions. Average position is the typical rank of your top result. Google notes that the chart uses a site-wide average, while the table averages per URL or per group.

The URL Inspection tool shows what Google has indexed for one page, including how Google found the URL and which canonical Google selected. You can run a live test after a fix, and you can ask Google to crawl the URL. Google warns that a request "does not guarantee that the page will appear in the Google Index."

What to check:

• It describes your own site only. Search Console shows no data for a competitor.
• It needs a verified property. You prove ownership of the site first.
• It reports Google only. Other engines need their own tools.

Bing Webmaster Tools

Bing Webmaster Tools does the same kind of job for Bing. It is a separate account with separate data. A site verified in one tool is not verified in the other, unless you import it. The setup steps, the sitemap submission and the IndexNow protocol are in Bing Webmaster Tools: setup, sitemaps and IndexNow.

Google Analytics

Search Console ends at the click. Google Analytics starts there. Google describes it as a platform that collects data from your websites and apps to create reports. You add a small JavaScript snippet to each page. The snippet records how a visitor interacted with the page, plus details such as browser, device and traffic source.

The two tools answer different questions, and neither replaces the other.

What to check:

• The two tools count different things. Search Console counts clicks from Google Search. Analytics counts visits to your pages from every source. Do not expect the two numbers to match.
• A tag must run on every page. A page without the snippet sends no data.
• Filters change stored data. Google notes that processed data cannot be altered later, so avoid excluding data you may want to analyze.

Strategist reads Search Console data and has a Google Analytics 4 tab, so both sit beside your rank data.

Keyword research tools

A keyword research tool shows what people search for and how often. It is the first job in the order of work, because it sets what you write.

What the data is

Keyword data comes from two kinds of source. The first is an engine's own ad system. The second is a vendor that estimates search volume with its own method.

Google's Keyword Planner is the first kind. It belongs to Google Ads. It suggests keywords related to your business, shows estimated searches per month, and shows the average cost to advertise on a keyword. Two limits matter for an SEO reader:

• You need a Google Ads account. Google says you must finish account setup, including billing information, to use basic features such as keyword ideas.
• It is built for ad campaigns. The cost and forecast columns describe advertising, not organic results. Google notes that campaign performance depends on factors such as bid, budget and ad quality.

Suites such as Semrush put keyword research in a named tool. The Semrush Knowledge Base lists a Keyword Magic Tool among its main tools. Each vendor's method for volume and difficulty is its own. The numbers from two vendors can differ for the same keyword, and neither is Google's number.

What to check

1. The source of volume. Is it the ad system or a vendor estimate? The documentation should say.
2. The meaning of difficulty. Vendors build their own difficulty score. One vendor's "hard" is not another's. Compare scores only within one tool.
3. Country and language. Volume for one country can differ from another. Set the location before you read a number.
4. What happens next. A keyword list is not a plan. Check whether the tool groups keywords by topic or sends them to a content plan.

On the last point, Strategist sends keyword research results, with volume and difficulty, into clusters of a pillar page and supporting articles. For the method, read keyword research for SEO and Google Keyword Planner.

Crawlers and site audit tools

A crawler fetches your pages the way a search engine does, then reports what it found. It answers a technical question: can a bot reach, read and understand every page?

What a crawler reports

A crawl audit follows links from page to page and looks for problems that hold a page back from search.

Typical checks include:

• Broken links and redirect chains.
• Missing or duplicate titles and meta descriptions.
• Pages with no incoming internal links (orphan pages).
• Pages that block bots or return error codes.

For the full process, read website crawlers and how to run a technical SEO audit.

Two crawlers and their limits

Crawlers differ most in where they run and what limit they set.

Screaming Frog SEO Spider is a desktop audit tool. Its page says it checks sites for over 300 issues. The free version crawls 500 URLs per crawl. A paid licence removes the limit. The product page also states that some features, such as saving crawls, depend on the licence, so read the licence comparison before you plan around a feature.

Ahrefs Webmaster Tools is a free offering for websites you verify. Ahrefs says its Site Audit scans for more than 170 technical and on-page issues. The limits are stated per project: Site Audit has 5,000 crawl credits per project per month, and only HTML pages that return status 200 use credits. The page also says the product has been renamed Ahrefs Free.

The two limits are not the same unit. One counts URLs per crawl. The other counts credits per month. A site of a few hundred pages fits either. A large site needs a calculation first.

Lighthouse and PageSpeed Insights

Two Google tools check page quality without a licence.

Lighthouse is an open-source tool that audits performance, accessibility, SEO and more. You can run it in Chrome DevTools, from the command line, as a Node module, or through PageSpeed Insights.

PageSpeed Insights reports two kinds of data. Read them apart.

Lab data is useful for debugging because it comes from a controlled environment. It can miss real-world problems. Field data reflects real users, but it covers fewer metrics. Google says the Core Web Vitals metrics are Interaction to Next Paint (INP), Largest Contentful Paint (LCP) and Cumulative Layout Shift (CLS). A page passes when the 75th percentile of all three is Good. For what to do about them, read Core Web Vitals.

What to check in any crawler:

• The crawl limit and its unit. URLs per crawl, or credits per month.
• JavaScript rendering. A crawler that does not render JavaScript cannot see content a script adds.
• Politeness. A good crawler reads robots.txt and limits its request rate. A crawl that overloads your server causes the harm you want to prevent.
• Where it runs. A desktop tool uses your machine. A cloud tool uses the vendor's servers, and your site sees the vendor's Internet Protocol (IP) address.

Strategist has a site-wide crawl audit that detects duplicate pages, orphan pages and redirects, and it can sample pages with Lighthouse.

On-page tools and plugins

On-page tools work on a single page while you write or edit. They check titles, descriptions, headings, images, links and structured data.

CMS plugins

A content management system (CMS) plugin sits inside your editor. The Yoast SEO features page lists what one major WordPress plugin offers. The list includes XML sitemaps, canonical URL tags, robots meta tags, breadcrumbs, redirects for attachment URLs, structured data, image alt text, internal linking blocks, a readability analysis and a keyphrase check. Other plugins list similar groups. WordPress SEO plugins compares what Yoast, Rank Math and All in One SEO control, from their documentation.

What to check:

• What the plugin writes to the page. Open the page source and read the result. A plugin setting is not proof of output.
• What the score means. A green light in an editor is the vendor's rule set. It is not a Google signal. Google's starter guide says there are no secrets that will automatically rank a site first, and it lists meta keywords, keyword stuffing and word-count targets as low priority.
• Plugin overlap. Two plugins that both write a sitemap or canonical tag can conflict.

Structured data and rich results

Structured data is markup that tells a search engine what a page contains. Google's supported structured data page says Google uses it to understand a page, and that it can make a page eligible for a richer display called a rich result. Google also says the actual appearance can differ, so markup does not guarantee a display. The same page links the Rich Results Test, a free Google tool that previews most features before you publish.

Titles, descriptions and links

The starter guide gives three rules you can check by hand:

• A good title is unique to the page, clear and concise.
• A good meta description is short, unique and covers the main points of the page.
• Link text describes the page it points to.

You do not need a tool for these on a small site. You can open each page and read the title and description yourself. A tool helps when you have hundreds of pages and need to find the ones that break a rule. That is a crawl job, not a writing job.

Content quality

No tool scores quality for Google. Google's people-first content guidance gives questions you answer yourself. For example: does the content give original information, and is it clear who made it and how? A tool that returns a "content score" measures the page against a vendor's model. Treat it as a checklist, not a prediction.

Rank tracking tools

A rank tracker records where your pages appear in search results for chosen keywords, over time. Search Console gives average position, but only for queries that already showed your site. A rank tracker lets you choose the keywords, the country and the device.

Where rank data comes from

Rank data comes from search engine results pages (SERPs). A vendor asks a search engine for a keyword and records where each URL appears. Some vendors run the queries and sell a tool. Some sell the raw results as an application programming interface (API).

The DataForSEO SERP API is an example of the second kind. Its documentation says it returns search results for a given keyword, search engine, language and location, and covers Google, Bing, YouTube, Yahoo, Baidu, Naver and Seznam. It offers two ways to collect results.

The documentation says Live returns results in real time at the highest cost, and Standard is more affordable but needs a separate POST and GET. This trade-off appears in most rank tracking products, even when the product hides it. For the build-or-buy decision, read rank tracking API. For a hands-on routine, read how to track keyword rankings, and for the tool field, rank tracking tools.

The Semrush Knowledge Base lists a Position Tracking tool next to its Keyword Magic Tool and Site Audit. That is the suite pattern: one subscription for several jobs, with one vendor's method for each.

What to check

1. Location. Results differ by country and city. Set both.
2. Device. Mobile and desktop results can differ.
3. Frequency. Daily data costs more than weekly data. Decide what change you need to see.
4. How the tool treats SERP features. Does it record only the blue links, or also featured snippets and local packs?
5. Export and history. Check that you can export the history before you rely on it.

Strategist tracks keyword positions daily, through a Playwright query or DataForSEO, and the page track rankings describes it.

Link tools

A backlink is a link from another site to yours. A link tool lists the linking sites, shows which links are new or lost, and flags links that look risky. The data source decides the quality of the answer.

First-party link data

The Search Console Links report shows top linked pages, top linking sites grouped by root domain, and top linking text. It also lists internal links. Google states these limits:

• Tables are limited to 1,000 rows.
• The report is not a comprehensive list of every link.
• Data is grouped by root domain.
• The report does not show which links are marked nofollow.

Third-party link data

A vendor builds its own link index by crawling the web. Coverage depends on the vendor's crawler. Ahrefs says its free Site Explorer shows which sites link to you, with 1,000 backlinks and keywords visible at once. A different vendor will show a different list for the same site, because each one crawls a different part of the web.

What to check:

• How fresh the index is. A new link may take time to appear.
• How "lost" is defined. A tool may mark a link lost when a crawler could not reach the page.
• What a risk score means. Treat it as a prompt to look at the link, not as a verdict.

Strategist reads its backlink profile from DataForSEO and lists new and lost links with a risk filter. The method is in backlink monitoring.

AI search visibility tools

A newer group of tools checks whether AI assistants and answer engines mention or cite your site. The method is simple: run a set of prompts, record the answer, and note which sources the answer names.

Two points apply. First, the output of an AI model changes between runs, so one result is a sample, not a measurement. Second, tools in this group are young, and their methods are not standardized. Ask each vendor which models it queries, how often, and how it picks prompts. Look at a trend over several runs, not a single answer, and read the cited sources to see which of your pages an engine used. A cited page tells you what to improve. A missing mention tells you where to look, not why.

Ahrefs states that the historical graphs in its Web Analytics include traffic from large language models (LLMs). That is a feature of an analytics product, not an answer-tracking tool, but it shows the first place to look: your own referral data.

Strategist runs prompts across OpenAI, Anthropic, Google, xAI, z.ai and Perplexity and records the sources each answer cites. For the method and the vendor field, read AI visibility tracking and AI SEO tools grouped by job.

Match the tool to the size of your site

The same tool behaves differently on a ten-page site and a ten-thousand-page site. Before you compare features, measure your site against the limits you read above.

• A small site. Google says a site of about 500 pages or fewer is small, and that a sitemap may not be needed if the pages link to each other. Search Console, Analytics and a free crawl cover most of the work. Screaming Frog's free crawl of 500 URLs fits inside that size.
• A medium site. Monthly allowances start to matter. A credit-based crawl limit, such as the Ahrefs Webmaster Tools allowance of 5,000 crawl credits per project per month, may run out if you crawl daily.
• A large site. Size limits, view limits and the Search Console tables of 1,000 rows begin to cut your data. You need an export path or an API, and you need to plan crawl load on your own server.

Read the Google sitemap guidance for the 500-page threshold. The threshold is Google's rule of thumb for when a sitemap helps, not a limit on tools, but it is a useful marker for where "small" ends.

Free and paid: what limits to read

Many tools offer a free tier. Free does not mean unlimited, and the limit tells you what the tool is for. The vendor pages cited above show three different kinds of limit.

Kind of limit	Example from vendor documentation	What it means for you
Size per run	Screaming Frog: 500 URLs per crawl in the free version	Fine for a small site, a block for a large one
Allowance per month	Ahrefs Webmaster Tools: 5,000 crawl credits per project per month	You can crawl often on a small site, and rarely on a large one
View limit	Ahrefs Site Explorer: 1,000 backlinks and keywords visible at once	You see a slice of the data
Account needed	Keyword Planner: a Google Ads account with billing information	Usable only after account and billing setup
Ownership needed	Search Console and Ahrefs Webmaster Tools: you verify your site	The tool works on your own sites only

Read the free tier as a statement of purpose. A tool limited to sites you own is built to audit your own site. A tool with a view limit is built to show you a sample and sell the rest.

What a paid tool adds

A paid plan usually removes a limit or adds a capability. Typical additions are:

• A higher or unlimited crawl size.
• Data on sites you do not own, such as a competitor.
• More tracked keywords, more locations or more frequent updates.
• Team access and reports.

Check each addition against your own need. A solo site owner rarely needs a feature that serves a team. Read the plan page for seat and project limits.

For a list of free tools by job, read free SEO tools.

How to choose tools

You do not need many tools. You need the right tool for each job you do. Use this order.

1. List the jobs you do each week. If you never track rankings, you do not need a rank tracker.
2. Use the official tool first. Search Console and Analytics are free of charge, and both hold first-party data. Add a third-party tool only when the official one cannot answer your question.
3. Check the limit against your site. Count your URLs, keywords and competitors. Compare them with the vendor's limit, in the vendor's unit.
4. Check where the data comes from. Ask whether the number is first-party, an estimate, or a sample.
5. Check how the data leaves. Can you export it? Can another tool read it through an API or a Model Context Protocol (MCP) server?
6. Check how the tool treats a rule. A rule is a score, a flag or a "fix". Open the documentation and read what the rule tests.

Suites and single tools

A suite groups several jobs under one login. The advantage is one place for the data. The cost is that each job uses the vendor's method, and a weak module still ships with the strong ones. Single tools do one job with more depth, but you join the data yourself.

The join is the part people underestimate. Keyword data lives in one tool, the page list in a crawler, the rank data in a tracker, and the traffic in Analytics. To act on them together, you copy numbers between tabs. When the join is manual, it happens less often than it should.

Strategist keeps keywords, clusters, the publish schedule, index status, rank and audit results in one workspace, and the page site owners describes the loop. For other roles, read SEO for small business and SEO tools for bloggers. To see the data from several tools in one view, read SEO dashboard.

Questions to ask a vendor

Put these questions to any vendor, or find the answers in its documentation:

• Which search engines and which countries does the data cover?
• How often does the data refresh?
• Is the volume or position figure measured or estimated?
• What happens to my data if I stop using the tool?
• Which limit will I hit first on my site?

If the documentation does not answer, treat the number as unverified.

Common mistakes when you adopt a tool

Four mistakes repeat. Each one is cheap to avoid.

• Reading a vendor score as a search engine signal. A difficulty score, a health score or a content score is the vendor's model. The engine does not publish or use it. Use the score to sort work, then confirm the problem on the page.
• Comparing numbers across tools. Two tools can report different volume or position for the same keyword. Pick one source for each metric and compare it only with itself over time.
• Judging a change too early. Google's starter guide says some changes take months. A drop or a rise in a week is rarely a result of your last edit.
• Adding a tool for every question. Each tool adds a login, a data silo and a limit to track. Add one only when a first-party tool cannot answer the question.

A short audit each quarter keeps the stack small. List every tool, name the job it does, and remove the ones that no decision used in that period.

Where tools fit in the weekly loop

A tool is only useful when it feeds a decision. The loop below shows where each group of tools gives its input.

1. Find. A keyword tool gives a list of topics. You pick the ones that match your site and your reader.
2. Publish. A CMS plugin or a publishing tool checks the page and sends it live.
3. Index. Search Console and Bing Webmaster Tools show whether the engine has the page. Submit the sitemap and read the coverage state. Strategist submits URLs to Google, Bing and Yandex and reads index status.
4. Measure. Search Console and Analytics show impressions, clicks and visits. A rank tracker shows position.
5. Fix. A crawler and the URL Inspection tool show what blocks a page. You change the page and publish again.

Google's starter guide says some changes take effect in hours and others take months, and suggests waiting a few weeks before you judge a change. Build that wait into the loop. Checking a page the day after an edit tells you little.

What the top results leave out

Most lists of SEO tools give a short description and a rating for each product. They leave out three things that decide whether a tool fits you:

• The unit of each limit. "Free" hides whether the limit is per crawl, per month or per view.
• The source of each number. A list rarely says whether a metric is first-party or estimated.
• The cost of the join. A list of ten tools does not show the work of combining them.

When you read any list, including this one, ask for those three answers before you decide.

FAQ

What is an SEO tool?

An SEO tool is software that does one job in search engine optimization. The job may be keyword research, crawling, page checks, rank tracking, link review or measurement. Some tools act on your site. Others only read data.

What makes a good SEO tool?

A good tool matches a job you do each week. It states where its data comes from, shows its limits in plain units, and lets you export your data. Check these points in the vendor documentation before you commit.

What about Google's SEO tools?

Google publishes these tools: Search Console, Analytics, PageSpeed Insights, Lighthouse, the Rich Results Test and Keyword Planner. Search Console and Analytics hold first-party data. Keyword Planner needs a Google Ads account.

Next steps

• Verify your site in Search Console: Search Console overview.
• Add Bing to your routine: Bing Webmaster Tools setup.
• Compare free tools by job: free SEO tools.
• Pick tools for your situation: SEO for small business.