At Moz, we love using premium SEO Tools (especially our own). Paid tools are essential when you need advanced features, increased limits, historical features, or online support.
For other tasks, a free tool does the trick.
Free Tools
1. Anchor Text Over Optimization Tool
http://www.removeem.com/ratios.php
Link Research, Technical SEO
Worried about Google’s Penguin algorithm hitting you for over-optimized anchor text? Simply type in your URL for a full report of which links might raise flags.
2. Bing Webmaster Tools
http://www.bing.com/toolbox/webmaster
Tools Suite, Diagnostic
Similar in function to Google Webmaster Tools, Bing offers a suite of interesting research tools and resources for webmasters.
3. Bitly
https://bitly.com/
Social, Analytics
Most people use Bitly for URL shortening, but the real power of this platform comes from its analytics.
4. Boomerang
http://www.boomeranggmail.com/
Email, Productivity
Boomerang lets you follow up on emails, even when you forget. Great for link building or any time you send a lot of emails.
5. Buffer
https://bufferapp.com/
Social
Optimize your online social media sharing. Buffer allows you to share with your audience at the optimal times for greater visibility.
6. BuiltWith
http://builtwith.com/
Competitive Intelligence
Use BuiltWith to discover what technology nearly any website was, well, built with. Great for competitive intelligence as well.
7. Buzzstream Tools Suite
http://tools.buzzstream.com/link-building
Link Building, Tools Suite, Email
Most people know Buzzstream as an outreach platform, but they also offer a number of free link-building tools. This company gets it.
8. Caption Tube
http://captiontube.appspot.com/
Video
Free and easy resource used to create captions for YouTube. Helps with usability and offers viewers a readable transcript.
9. CircleCount
http://www.circlecount.com/
Social, Analytics
Google+ analytics ramped up. Free resource to track your followers and analyze your shares. See how many followers you’ve gained over time.
11. Convert Word Documents to Clean HTML
http://word2cleanhtml.com/
Content, Productivity
Despite the rise of Google Docs, Word still dominates much of the world. Copying and pasting has always been a hurdle, but this tool makes it easy.
12. Copyscape
http://www.copyscape.com/
Content
Copyscape serves both as a plagiarism checker and a duplicate-content checker. Great to use if your content has been distributed across the web.
13. Domain Hunter Plus
http://domainhunterplus.com/
Link Building
This magic extension for Chrome not only helps you find important broken links, but also tells you if the links point to an available domain.
14. Easel.ly
http://www.easel.ly/
Infographics
Free tools for creating and sharing inforgraphics. The templates allow anyone to create a professional-looking graphic.
15. Email Format
http://email-format.com/
Email, Productivity
Email Format helps you find the proper structure for thousands of companies and organizations across the web.
16. FindPeopleonPlus
http://www.findpeopleonplus.com/
Social
The ultimate Google+ directory that’s great for research, outreach, and link building. Sort by keywords, profession, country, and more.
17. Frobee Robots.txt Checker
http://www.frobee.com/robots-txt-check
Robots.txt, Technical SEO
Many robots.txt files contain hidden errors not easily visible to humans. Run your file through this tool and you never know what you’ll discover.
18. GetListed
https://getlisted.org/
Local, Moz
This awesome local SEO tool scores your local SEO visibility and gives you actionable next steps to raise your score.
19. Google Keyword Planner
http://adwords.google.com/keywordplanner
Keyword Research
The tool to replace Google’s popular keyword tool has been derided by some, but still offers data not available anywhere else.
20. Google Analytics
http://www.google.com/analytics/
Analytics
The most popular of all the analytics tools available, Google Analytics continually innovates and sets the standard.
22. Google Map Maker
http://www.google.com/mapmaker
Local
Among other things, Google Map Maker allows you to contribute to public map information, which may be shared and incorporated into Google Maps.
25. Google SERP Snippet Optimization Tool
http://www.seomofo.com/snippet-optimizer.html
Technical SEO, CRO
That SEO Mofo! Use this tool to see how your snippet may appear in Google’s search results. Add structured data, review stars, and more.
27. Google Trends
http://www.google.com/trends/
Keyword Research
See what’s trending in Google search results and view keyword search popularity over time. A must for trends.
28. Google Webmaster
http://www.google.com/webmasters/
Tools Suite, Diagnostic
The interface recently received an overhaul, and Google Webmaster remains a must-have resource of diagnostic and health tools for site owners.
29. IFTTT
https://ifttt.com/
Productivity
IFTTT stands for IF This, Then That. The tool allows you to create automatic triggers between various apps, like Gmail and Twitter.
30. Infogr.am
http://infogr.am/
Infographics
A great free Infographics resource that allows you to easily create graphics and data visualizations.
32. Linkstant
http://www.linkstant.com/
Link Building
This nifty analytics tool alerts you anytime someone links to your website. Great for outreach and intelligence gathering.
33. Linksy.me Email Guesser
http://linksy.me/find-email
Email, Link Building
Need to send an email, but you don’t have the recipient’s address? Type in what you know and this nifty tool will help you figure it out.
34. MailTester.com
http://mailtester.com/
Email
Need to send an email to an untested address, but you don’t want to spam them? Check it first with this mail tester to verify.
35. MozCast
http://mozcast.com/
SERP Tracking, Moz
Want to know if Google is testing its algorithm this week? MozCast gives you a daily weather report to track changes in the SERPs.
36. MyBlogGuest
http://myblogguest.com/
Link Building, Content
Guest blogging is still alive and thriving. MyBlogGuest helps you find the good opportunities out there.
38. Pingdom
http://tools.pingdom.com/fpt/
Speed
Pingdom offers an entire suite of speed tools to help analyze page load, DNS issues, and connectivity.
39. Piwik
http://piwik.org/
Analytics
Piwik is a lightweight web analytics solution, and a great alternative to Google Analytics.
41. Rapportive
http://rapportive.com/
Email, Link Building, Productivity
Rapportive works with your Gmail inbox to give you near-instant rich contact information for almost everyone you want to reach. A must-have for marketers.
42. Remove Duplicate Items
http://ontolo.com/tools-remove-duplicates
Productivity
Ontolo offers a suite of link building software and a few helpful productivity tools for link builders. The remove duplicates tool solves a common problem.
44. Schema Creator
http://schema-creator.org/
Structured Data, Technical SEO
Everyone loves using Schema.org, but the microformats are difficult to write by hand. This generator from the folks at Raven simplifies the task.
46. Seer Toolbox
http://www.seerinteractive.com/seo-toolbox/
Tools Suite, Analytics, Link Research
SEER opened up its internal toolbox for everyone in the world to use. These are the same tools used in-house at SEER, and they rock.
47. SEO Toolbar
http://tools.seobook.com/seo-toolbar/
Tools Suite, Toolbar, Technical SEO
On of the most popular tools available, The SEO Toolbar puts a ton of information at your fingertips including backlinks and competitive research.
48. SEO Tools for Excel
http://nielsbosma.se/projects/seotools/
Tools Suite, Analytics, Social
You don’t need to be an Excel ninja to use Niels Bosma’s SEO Tools for Excel. This plugin does so many things many SEOs won’t work without it.
49. SEOgadget Links API
http://seogadget.com/api/
API, Link Research
The SEOgadget Links API lets you easily gather not only backlink data but contact information as well. A huge time saver.
50. SEOgadget Tools
http://seogadget.com/tools/
Tools Suite
This suite of tools from the Gadget lab includes several Excel plugins, a content strategy generator, and more.
51. SEOQuake
http://www.seoquake.com/
Toolbar, Tools Suite, Technical SEO
More raw data than any other SEO toolbar out there.
52. SharedCount
http://www.sharedcount.com/
Social, Analytics
Want to know how any piece of content was shared socially across the major services? This is the tool to use.
54. Similar Page Checker
http://www.webconfs.com/similar-page-checker.php
Content, Technical SEO
Use this tool to check for duplicate content issues. The Similar Page Checker will give you a score of how closely the HTML of two pages resemble each other.
56. Social Authority API
https://followerwonk.com/social-authority
API, Social
How much reach and social authority do your followers have? How about the people you’re trying to connect with? The free Social Authority API will tell you.
57. Social Crawlytics
https://socialcrawlytics.com/
Social, Analytics
Social Crawlytics allows you to conduct competitive research by showing you your competitors’ most-shared content. Lots of other features as well.
58. Social Mention
http://www.socialmention.com/
Social
Social mention offers real-time social media search and analysis. Enter a search term and see who’s sharing what, right now.
59. Text Cleaner
http://www.textcleanr.com/
Content
Some of the best tools solve the simplest problems. Text cleaner cleans up all kinds of text formatting when copying and pasting between aplications.
60. Ubersuggest
http://ubersuggest.org/
Keyword Research
Every SEO loves Ubersuggest for its ease of use and wealth of keyword research ideas. Utilizing the power of Google Suggest, it returns hundreds of potential results.
61. URI Valet
http://urivalet.com/
Technical SEO
A great tool for digging into server headers, canonical information, analyzing redirect problems and more.
62. Virante SEO Tools
http://www.virante.org/seo-tools
Tools Suite
Virant offers a number of high quality SEO tools to the public. These are often the same tools developed for the Virant team, opened up for public use.
63. Wayback Machine
http://archive.org/web/web.php
Competitive Intelligence
Want to see the history of your website or your competitor’s site? The Wayback Machine allows you to step back in time and track important changes.
65. Wordle
http://www.wordle.net/
Content
Create beautiful word clouds. Great for visualizations, graphics, and research.
66. Wordstream Free Keyword Tools
http://www.wordstream.com/free-keyword-tools
Keyword Research, Tools Suite
In addition to its paid offerings, Wordstream offers a suite of free keyword tools offering access to thousands of keyword suggestions.
67. Xenu’s Link Sleuth
http://home.snafu.de/tilman/xenulink.html
Diagnostic, Technical SEO
Winner of the ugliest-SEO-tool-on-the-planet award, Xenu is also one of the most useful. Crawl entire sites, find broken links, create sitemaps, and more.
68. XML-Sitemaps.com
http://www.xml-sitemaps.com/
Sitemaps
XML-Sitemaps offers probably the easiest sitemap creation solution anywhere. Great for smaller sites when you need a sitemap in minutes.
69. Yahoo Pipes
http://pipes.yahoo.com/pipes/
Content, Productivity
A great mashup tool that combines different feeds into content and other magical creations. Used for link building and whatever you can dream of.
70. Yoast WordPress SEO Plugin
http://yoast.com/wordpress/seo/
Technical SEO
If you could only choose one WordPress plugin for you site, the first would be from Yoast, and so would the second. This one sets the standard.
71. YouTube Analytics
https://www.youtube.com/analytics
Video, Analytics
Offers video-specific analytics for YouTube videos. A must-have for YouTube video publishers.
Free and Paid
72. Ahrefs
https://ahrefs.com/
Link Research, Link Building
One of the more popular link research tools, Ahrefs offers a large index and nice anchor text distribution charts. Mostly a paid tool, but they offer some free data.
73. Banana Tag
http://bananatag.com/
Email
Banana Tag allows you to track your emails after you send them. For example, check your email open rates from Gmail.
74. CloudFlare
https://www.cloudflare.com/
Speed
How do they make CloudFlare free? It works both as a CDN and a security service to provide your website with speed and safety.
75. Followerwonk
https://followerwonk.com/
Social, Analytics, Moz
Perhaps the coolest thing about Followerwonk is the ability to track your followers. Smart SEOs also use it for outreach and research.
76. Keyword Eye
http://www.keywordeye.com/
Keyword Research
Keyword eye adds a twist to keyword research by adding rich visualizations — essential when you want to move beyond keywords to valuable concepts.
77. KnowEm
http://knowem.com/
Social
KnowEm allows you to check 100’s of social profiles at once to check availability. Looking for the perfect brand name? Check KnowEm first.
78. Majestic SEO
http://www.majesticseo.com/
Link Research, Competitive Intelligence, Link Building
You’ve probably seen Majestic SEO link charts all over the Internet. Great crawling technology combined with several free options make for great link research.
80. MozBar
http://moz.com/tools/seo-toolbar
Tools Suite, Toolbar, Moz
The standard SEO toolbar for legions of marketers, the MozBar allows you to perform over 50 key tasks right from your browser. Highly recommended.
81. Mozscape API
http://moz.com/products/api
API, Link Research, Moz
Companies everywhere incorporate the Mozscape API into their own products, but it’s also available to individuals, and much of the data is free.
82. nTopic
http://www.ntopic.org/
Content
nTopic is one of the few proven methods for giving your content a relevancy score and offering keyword suggestions to improve it.
83. Open Site Explorer
http://www.opensiteexplorer.org/
Link Research, Moz, Competitive Intelligence, Link Building
When Google and Yahoo started removing backlink data from the public, Moz built Open Site Explorer to fill a huge need. See backlinks, anchor text, popularity metrics and more.
84. Piktochart
http://piktochart.com/
Infographics
A cute and easy infographic generator. No experience required.
85. RowFeeder
https://rowfeeder.com/
Social, Analytics
RowFeeder allows you to track social usernames, hashtags and keywords and load that information into Excel for easy social media monitoring.
86. Screaming Frog
http://www.screamingfrog.co.uk/
Diagnostic, Technical SEO
A powerful website crawling tool with a ton of features and customizations. A must-have for most serious SEOs.
87. Searchmetrics Visibility Charts
http://suite.searchmetrics.com/en/research
SERP Tracking, Competitive Intelligence
Track the search visibility of any website, in addition to tracking winners and losers in Google’s search results.
88. SEMrush
http://www.semrush.com/
Tools Suite, Keyword Research, Competitive Intelligence
The paid and organic keyword data offered by SEMrush is often scary good and comprehensive. Also great for researching competitors’ ads.
89. SERPmetrics
http://serpmetrics.com/flux/
SERP Tracking, Competitive Intelligence
SERPmetrics flux charts track the flux for US search results across Yahoo, Bing and Google over a 30-day period. A paid API is also available.
90. SimilarWeb
http://www.similarweb.com/
Competitive Intelligence
Impressive competitive intelligence across a number of online industries. Competitor website stats are hard to come by, but Similar Web does a good job.
91. StatCounter
http://statcounter.com/
Analytics
Free, quick, and lightweight analytics solution. Often used by those who want to avoid using Google Analytics for privacy reasons.
92. Trello
https://trello.com/
Productivity
Project management and tracking made simple. Used and endorsed by Moz.
93. Whitespark Local Citation Finder
https://www.whitespark.ca/local-citation-finder/
Local
Finding local citations is key to local SEO. Whitespark offers a number of free and paid solutions to find the local citations to rise above the competition.
94. Whois Lookup
http://whois.domaintools.com/
Competitive Intelligence
Find registration, contact, and administrative information for any domain.
95. Wistia
http://wistia.com/
Video
The king of online video, Wistia offers SEO-friendly solutions for video hosting. Both free and low-cost options available.
Free Trials
96. Moz Analytics
http://moz.com/products
Tools Suite, Diagnostic, Moz, Rank Tracking, Social
The flagship of the Moz software suite, Moz Analytics offers a dashboard of all your important marketing data in one place with actionable analytics for better marketing.
97. Optimizely
https://www.optimizely.com/
A/B Testing, CRO
Easy A/B testing and analytics to help you move toward success in your CRO efforts.
98. Raven
http://raventools.com/
Tools Suite, Diagnostic, Content, Social
Raven offers a classic suite of SEO, content, and research tools popular with many marketers.
99. Visual Website Optimizer
https://visualwebsiteoptimizer.com/
A/B Testing, CRO
Visual Website Optimizer allows you to run A/B tests with a simple online editor that lets you test content without knowing code.
100. Wordtracker
http://www.wordtracker.com/
Keyword Research
A powerful keyword research suite used by many top marketers, Wordtracker offers a generous free trial option.
Narrowing a list down to the 100 best SEO tools and resources is not an easy challenge. Although I visited hundreds of webpages to compile this list, these four resources offered particular value:
Despite researching hundreds of tools, a few great ones didn’t make the list. What’s your favorite free SEO tool? Let us know in the comments below.