The 15 best free SEO tools

We asked a set of SEO experts and search marketing professionals about their favorite SEO tools and came up with these 15 recommendations. And the price sure is right: They are all free.

01 seo title
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Free SEO tools worth trying

Keeping up with search engine optimization (SEO) trends can be time-consuming — but it doesn't have to be wallet-draining. Fortunately, tons of free cloud-based SEO tools and downloadable applications exist that can make the job easier.

We reached out to the SEO community for recommendations on free tools, including utilities for both keyword and backlink research. Some of the following 15 SEO tools are well-known, and you may not have heard of others, but all of them are worth a try, according to our sources. And all are free, at least to some extent — some give you limited tool access, after which you have to cough up a credit card number. However, even the free versions are useful enough to warrant a recommendation.

02 screaming frog
Screaming Frog SEO Spider for SEO audits

Screaming Frog SEO Spider is a popular free software download that lets you perform a variety of tasks, with a focus on technical website audits designed to uncover problems that might adversely impact search engine rankings. "It's a really detailed tool and very simple to use," says Philip Elliot, ecommerce and marketing manager at We Sell Electrical.

The tool does a complete crawl of your site. "The list of elements it looks at is exhaustive and insightful, from meta data, meta robot tags and canonical tags to response time, word count and status codes." Elliot recommends using the software's Google SERP snippets optimization feature (shown). The software is free, but it limits you to 500 URL crawls. Annual licenses cost roughly $150.

03 semrush
SEMrush for competitive analysis and keyword research

SEMrush's free tools provide insights into keyword performance, such as which sites rank in Google's top 100 results for a given keyword. You can also plug in URLs to get information on sites' traffic, keyword ads, organic versus ad traffic, organic keywords, and more.

SEMrush "presents you with detailed engagement metrics [and] backlink information, as well as keyword targeting information, on any given website," says Elliot of We Sell Electrical. "We use it to make informed decisions on our on-site and off-site SEO. SEMrush has premium features, but the free version is still very useful." Paid plans cost $70 a month.

04 ubersuggest
Ubersuggest for keyword research

Ubersuggest is like Google's keyword-suggestion and autocomplete feature "on steroids," according to its developer. Type in a keyword, select a language and content type (such as Web, images or news), and the tool suggests related terms that searchers used on Google and other sites.

Marcus Miller, head of SEO, PPC and digital marketing for BowlerHat, says he uses Ubersuggest and Google's Keyword Planner tools together. "Ubersuggest will help you generate ideas and expand your base set of keywords into a hugely diverse set of options," he notes. "You can then run these keywords through Google Keyword Planner to get more detailed metrics and fine tune these metrics to your own specific situation."

05 google keyword tool
Google Keyword Planner for keyword research

Google's Keyword Planner is still "the go-to source to discover a keyword's search volume and

Competitiveness, and to get insight on the average cost-per-click," says Christian M. Habermann, founder of Auctus Marketing. Using the tool, "you can really discover which keywords will be the most effective to target for your business. This tool can also be helpful in finding long-tail keywords — which are often the gems."

Habermann sometimes puts a competitor's site into the tool's URL box to see which keywords are prominent on that site. "This tool is very powerful, and every SEO ought to be using it for keyword research."

06 kwfinder
KWFinder for keyword research

KWFinder helps you uncover long-tail keywords with low SEO competition. You can perform five searches per day, of up to 50 keywords per search, for free. The tool "can completely change your belief around how people are searching," says Tim Detmer, founder of Jiffy Rank. "You can type in your ideal query and it will give you Google search traffic numbers, cost-per-click estimates, and their SEO difficulty scores, which are a great gauge on how difficult it will be to break onto the first page of search results." KWFinder also generates related searches, according to Detmer. Paid plans start at $29 per month.

07 google search console
Google Search Console for website maintenance

Formerly called Google Webmaster Tools, Google Search Console is well-known but "sometimes overlooked and underrated," says Steve Morgan, freelance SEO consultant, Morgan Online Marketing.

Google Search Console is free, and it's useful for determining site errors that can adversely affect your Google search result rankings. "It can point out errors such as 404/Page Not Found errors that Screaming Frog SEO Spider might have missed. You can also use its 'Fetch as Google' tool to ask Google to re-crawl a URL, or your whole site again, which might end up happening quicker than if they did it naturally." The Fetch as Google tool works for mobile and desktop sites.

08 seocentro seo analyzer
SEOCentro SEO Analyzer for website and content analysis

SEOCentro's SEO Analyzer is "a brilliant free SEO tool that I recommend at all my speaking events," says Shannon K. Steffen, founder and CEO of Daymark Digital. "Although it won't tell you how to fix SEO problems on your website, it will give you a great snapshot of what's broken and what's working. Make sure to scroll to the bottom to see what your top keywords are on that Web page. If your top keyword is 'read more,' you'll want to work on content optimization."

09 panguin
Panguin for Penguin and Panda checks

U.K.-based Barracuda Digital's free Panguin tool analyzes websites and checks for a variety of issues, including possible impact from Google's Penguin and Panda updates. The "awesome" tool taps into your Google Analytics account and "specifically looks at organic traffic only," according to Maria Fiscina, SEO department manager of Active Web Group. Panguin is "especially helpful when assessing a site's trending performance," she says.

10 website penalty indicator
Website Penalty Indicator for Penguin, Panda and mobile-friendly checks

Another recommended tool for checking Google penalties is the Website Penalty Indicator, which graphs a site's organic traffic against a timeline of Penguin, Panda, and mobile-friendly algorithm updates, says Anthony D. Nelson, owner of Northside SEO. "If you're considering purchasing a domain or simply want to do some competitive research, this tool gives you quick and easy insights to see if it has been affected by any of Google's big algorithm updates."

11 yoast seo
Yoast SEO for WordPress site optimization

Yoast SEO is a free plug-in for WordPress.org blogs and websites, and it's "an absolute must," according to Morgan of Morgan Online Marketing. "It gives you the option to change the page title and metadata for individual pages or posts, and gives you basic SEO guidance based on your desired keyword while helping you create and customize XML sitemaps, among many other things." The plug-in provides feedback on your SEO efforts for posts and pages using green, yellow, and red circles.

12 seo spyglass
SEO SpyGlass for competitive analysis and backlink analysis

SEO SpyGlass, a free software download, "is essential for monitoring a website's backlink profile and to find out the sources for a competitor's backlinks," says Michelle Symonds, SEO Consultant at DittoDigital. "It produces a huge amount of detail, more than any other similar tool I've tried. The amount of data you can collect, and where it is collected from, is all under your control. Also, when you choose to collect the data is under your control."

Unlike most similar tools, you can run an analysis at irregular intervals instead of a regular cycle. "This is especially important if some major change has taken place and you want an updated report quickly," she says. Paid access to additional features requires a one-time fee of either $124.75 or $299.75, depending on feature sets.

13 moz open site explorer
Moz Open Site Explorer for backlink analysis and website authority

Moz's SEO tools are mostly available in paid plans that cost $99 a month or more. However, you can use one of its more compelling features, Open Site Explorer, for free. Open Site Explorer is a "brilliant" link analysis tool that provides "insight into your website's inbound links, authority, page link metrics, top pages, linking domains, and top landing pages," according to Steffen of Daymark Digital.

The tool also gives you a handle on the authority of an entire site or a particular page. "By knowing these data points, you can further optimize pages with already existing authority so that they convert better, and you can create a link-building strategy that will further increase your authority online," Steffen says.

14 varvy seo tool
Varvy Seo Tool for website and content analysis

The free Varvy Seo tool provides various glimpses into how your website and content are performing, from the number of domains linking to yours to recent social media mentions. "Just plug in any page on your website and watch the SEO results come in," says Alexander Munsell, SEO analyst and head of digital marketing for Anchour Creative. "The tool helps provide further insight into areas of greatest concern, such as image optimization, content optimization, website technological issues, website speed, and links."

15 ga custom reports
Google Analytics for custom reports

Google Analytics (GA) is probably the best-known free suite of SEO tools, but its custom reporting tool is often underused or not used at all, according to Munsell of Anchour Creative. GA's Custom Reports let you choose dimensions, such as city, and metrics, which can include bounce rates and page views, to get a real-time, customized look at site performance. For example, GA's Custom Reports let Munsell easily see which day of the week is most popular for each gender and age group visiting a client's site, and who in each demographic converts the most, he says. When combined with other tools from Google Analytics and Moz, Munsell says he can "figure out why a specific demographic is or isn't converting."

16 tineye
TinEye for reverse image search

TinEye is a free "reverse image search" tool that's handy for image search SEO strategies. "Part of my backlink strategy is to submit high-quality images on behalf of clients to stock image sites, and later check who has used those images with TinEye," says Anchour Creative's Munsell. "I'll email the site's owner and explain how my clients own the original image, and ask if they'd be willing to link to their site. I use TinEye's Chrome plug-in so that I'm able to right-click an image to have TinEye look across the Web for it." (Firefox, Safari, IE and Opera also have TinEye plug-ins.)