1. Anchor Text Over Optimization Tool
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
Tools Suite, Diagnostic
Similar in function to Google Webmaster Tools, Bing offers a suite of interesting research tools and resources for webmasters.
Most people use Bitly for URL shortening, but the real power of this platform comes from its analytics.
Boomerang lets you follow up on emails, even when you forget. Great for link building or any time you send a lot of emails.
Optimize your online social media sharing. Buffer allows you to share with your audience at the optimal times for greater visibility.
7. Buzzstream Tools Suite
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.
Google+ analytics ramped up. Free resource to track your followers and analyze your shares. See how many followers you’ve gained over time.
10. Content Strategy Generator Tool
This tool from SEOgadget helps you plan your content strategy intelligently, using keyword research and estimating your audience size.
11. Convert Word Documents to Clean HTML
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.
13. Domain Hunter Plus
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.
17. Robots.txt Testing Tool
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.
19. Google Keyword Planner
The tool to replace Google’s popular keyword tool has been derided by some, but still offers data not available anywhere else.
21. Google Analytics API
The Google Analytics API is great for building custom reports and tools, and also for pulling data straight into Excel or Google Docs.
22. Google Map Maker
Among other things, Google Map Maker allows you to contribute to public map information, which may be shared and incorporated into Google Maps.
23. Google PageSpeed Insights
Tools, data, and insights to improve your page speed. Page speed is correlated with better rankings and user engagement, so this matters.
24. Google Public Data
Drawing on vast public databases, Google public data offers a great starting point for content research, infographics, and more.
25. Google SERP Snippet Optimization Tool
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.
26. Google Structured Data Testing Tool
Structured Data, Technical SEO
If you use Schema.org microformats or any other type of structured data, this tool will verify your markup.
28. Google Webmaster
The interface recently received an overhaul, and Google Webmaster remains a must-have resource of diagnostic and health tools for site owners.
31. Internet Marketing Ninjas SEO Tools
The Ninjas are some of the best SEOs and online marketers out there, and they’ve put some of their best tools online for free.
33. Linksy.me Email Guesser
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.
37. Panguin Tool
This awesome tool connects with your Google Analytics account to help you see if and when you’ve been hit by Google Algorithm updates.
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
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.
43. Robots.txt Checker
Robots.txt, Technical SEO
Use robots best practices and discover hidden errors in your robots.txt files that may cause search engine crawling problems.
44. Schema Creator
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.
45. Scraper for Chrome
If you’ve never scraped a webpage, you’re missing out. Scraper for Chrome puts the power of simple web scraping in your hands without the need for code.
46. Seer 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
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
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.
53. SharedCount API
Harnessing the combined statistics of Google+, Twitter, Facebook, and more, the SharedCount API puts a ton of social data at your fingertips.
54. Similar Page Checker
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.
55. Sitemap Generators
Google offers a slew of free, top-notch sitemap generators. Most of these live on your server and generate new sitemaps automatically.
56. Social Authority API
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
Social Crawlytics allows you to conduct competitive research by showing you your competitors’ most-shared content. Lots of other features as well.
59. Text Cleaner
Some of the best tools solve the simplest problems. Text cleaner cleans up all kinds of text formatting when copying and pasting between applications.
60. Keyword Explorer
Moz’s newest free tool offers some of the most accurate keyword volume you can get, plus tons of keyword and topic suggestions at the click of a button. Syncs with Moz Pro site tracking to inform your SEO strategy as a whole.
62. Virante SEO Tools
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
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.
66. Wordstream 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
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.
69. Yahoo Pipes
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
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.
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.
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
Keyword eye adds a twist to keyword research by adding rich visualizations — essential when you want to move beyond keywords to valuable concepts.
78. Majestic SEO
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.
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
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.
83. Open Site Explorer
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.
87. Searchmetrics Visibility Charts
SERP Tracking, Competitive Intelligence
Track the search visibility of any website, in addition to tracking winners and losers in Google’s search results.
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.
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.
Impressive competitive intelligence across a number of online industries. Competitor website stats are hard to come by, but Similar Web does a good job.
93. Whitespark Local Citation Finder
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.
96. Moz Pro
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.
99. Visual Website Optimizer
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.