SEO course › Part 1: SEO foundations
SEO tools are software that help you research keywords, check how your site is performing, find technical problems and study competitors. Free tools from Google and Bing show data about your own site. Paid SEO tools such as Ahrefs, Semrush and Moz add estimates about the wider web, including competitor keywords and backlinks.
This lesson covers the types of SEO tools, the free tools every site should use, the best-known paid platforms, and how to choose what you need without overspending.
What do SEO tools actually do?
Most SEO tools do one or more of these jobs:
- Keyword research: finding what people search for and how often.
- Rank tracking: checking where your pages appear for chosen keywords over time.
- Site auditing: crawling your site to find technical issues such as broken links, missing titles or slow pages. Crawling means a program visiting your pages one by one, as a search engine would.
- Backlink analysis: showing which websites link to you or to competitors. A backlink is a link from another site to yours.
- Competitor research: estimating which keywords bring traffic to other sites.
One important point: data about your own site from Google is real measurement. Data about other sites from third-party tools is always an estimate.
Which free SEO tools should every site use?
Start with these before paying for anything.
- Google Search Console: real queries, clicks, indexing status and issues for your site in Google.
- Google Analytics 4: what visitors do after they arrive.
- Bing Webmaster Tools: Bing data, plus a free Site Scan audit and backlink reports.
- PageSpeed Insights: page speed and Core Web Vitals scores for any URL.
- Rich Results Test: checks whether your structured data can produce enhanced search results.
- Google Keyword Planner: keyword ideas and volume ranges, available through a Google Ads account.
For many small businesses, these free tools are enough for the first year.
What are the most popular paid SEO tools?
Ahrefs
Ahrefs is known for its large backlink index and its Site Explorer, which shows the keywords and links behind any domain. It also offers Keywords Explorer, Rank Tracker and Site Audit. Ahrefs Webmaster Tools gives verified site owners free access to site audit and backlink data for their own sites.
Semrush
Semrush is an all-in-one platform covering keyword research, position tracking, site audits, backlink analysis and competitor research. Many agencies use it because it also covers paid search and content planning in one place.
Moz
Moz Pro offers keyword research, rank tracking and site crawls. Moz created the Domain Authority metric and the free MozBar browser extension, which shows metrics while you browse.
Screaming Frog SEO Spider
Screaming Frog is a desktop crawler you install on your computer. It is excellent for technical audits: finding broken links, redirect chains, duplicate titles and missing meta descriptions. The free version crawls up to 500 URLs, which covers most small sites.
Ubersuggest
Ubersuggest is a budget-friendly tool with keyword ideas, site audits and basic competitor data. It offers limited free searches per day, which makes it a gentle starting point.
How do the main SEO tools compare?
| Tool | Best known for | Free option | Good for beginners? |
|---|---|---|---|
| Ahrefs | Backlinks and competitor keywords | Ahrefs Webmaster Tools for your own site | Yes, once you know the basics |
| Semrush | All-in-one SEO and competitor research | Limited free account | Yes |
| Moz | Domain Authority and keyword research | MozBar and limited free searches | Yes |
| Screaming Frog | Technical site crawling | Free up to 500 URLs | Moderate, it is technical |
| Ubersuggest | Affordable keyword ideas | Limited daily searches | Very beginner friendly |
Prices and plans change often, so check each tool’s own website before you buy.
What do metrics like Domain Authority mean?
Paid tools create their own scores, such as Moz’s Domain Authority, Ahrefs’ Domain Rating and Semrush’s Authority Score. These try to estimate how strong a site’s backlink profile is.
Google has said it does not use these third-party scores. They are useful for comparing sites, not as goals in themselves. Similarly, keyword volumes and traffic estimates are modeled, so two tools can show very different numbers for the same keyword.
A worked example: an online saree shop
Imagine an online saree shop run by two people from Surat. Their budget is tight.
They start with Search Console and see impressions for “Banarasi silk saree online” but a low click-through rate. They rewrite the page title and description. Next, they run Screaming Frog’s free version and find broken links on old product pages. They fix them and add redirects.
After six months, they want to understand competitors. They take a one-month plan on a paid tool, export competitor keyword gaps for festival collections, then cancel. They spend only when they have a clear question to answer.
How do you choose the right SEO tools?
- Set up the free Google and Bing tools first.
- Write down the questions you cannot answer with free data.
- Try free trials or free tiers of one or two paid tools.
- Choose the tool whose reports you actually understand and use.
- Review the subscription every few months and cancel if unused.
AI features are now common inside these tools, helping with content briefs and keyword grouping. Treat AI suggestions as a starting point, as our artificial intelligence section discusses.
Common mistakes to avoid
- Paying for an expensive tool before setting up Search Console.
- Treating keyword volumes and traffic estimates as exact numbers.
- Chasing a higher Domain Authority score instead of better content and links.
- Fixing every audit warning, even minor ones, instead of the issues that affect users.
Key takeaways
- SEO tools help with keywords, rankings, audits, backlinks and competitor research.
- Free tools from Google and Bing measure your own site with real data.
- Ahrefs, Semrush and Moz estimate data about the wider web; Screaming Frog crawls sites; Ubersuggest is budget-friendly.
- Third-party scores are not Google ranking factors.
- Buy paid SEO tools only when you have questions free tools cannot answer.
Frequently asked questions
Can I do SEO without paid tools?
Yes. Many small sites grow using only Search Console, GA4, Bing Webmaster Tools and free crawlers. Paid tools mainly save time and add competitor data.
Which SEO tool is best for beginners?
There is no single best tool. Start with Google Search Console, then try the free tier of Ubersuggest, Semrush or Ahrefs Webmaster Tools to see which interface you find easiest.
Why do SEO tools show different search volumes?
Each tool uses its own data sources and models to estimate volume. Use the numbers to compare keywords relative to each other, not as exact counts.
Previous lesson: Bing Webmaster Tools: set up Bing and reach other search engines
Next lesson: Domain name for SEO: how to choose one that helps your site grow