Answer of this all SEO queries solved, here are some of my favorite and free SEO and other general purpose marketing tools (some of them are paid for more functionality) that will help you do marketing more easily than ever.
SEO Tools
Varvy: https://varvy.com/Moz: https://moz.com/free-seo-tools
Small SEO Tools: http://smallseotools.com/
Screaming Frog: https://www.screamingfrog.co.uk/seo-spider/
Google Webmaster Tools: https://www.google.com/webmasters/
Google PageSpeed Insights: https://developers.google.com/speed/pagespeed/insights/
Google Structured Data Testing Tool: https://search.google.com/structured-data/testing-tool/u/0/
Bing Webmaster Tool: http://www.bing.com/toolbox/webmaster
QuickSprout: https://www.quicksprout.com/
SimilarWeb: https://www.similarweb.com/
BrowSeo: http://www.browseo.net/
SEO SiteCheckup: https://seositecheckup.com/
Robots.txt Genertaor: http://www.yellowpipe.com/yis/tools/robots.txt/
XML Sitemap Generator: https://www.xml-sitemaps.com/
Bulk DA Alexa Checker: http://www.freebulkseotools.com/bulk-pr-da-alexa-checker.php
Xenu’s Link Sleuth: http://home.snafu.de/tilman/xenulink.html
REDbot: https://redbot.org/
Keyword Density Checker: https://www.seocentro.com/tools/seo/keyword-density.html
SEO Workers: http://www.seoworkers.com/tools/analyzer.html
WooRank – SEO Audit: https://www.woorank.com/
Found – SEO Audit Tool: https://www.found.co.uk/seo-tool/
SEMrush: https://www.semrush.com/
SERPs Rank Checker: https://serps.com/tools/rank-checker/
Remove’em – Anchor Text Optimization Tool: https://www.removeem.com/anchor-text-ratios/
JSON-LD Schema Generator: https://hallanalysis.com/json-ld-generator/
SEO Quake: https://www.seoquake.com/index.html
AuthorityLabs – SEO Tracking: https://authoritylabs.com/
DeepCrawl: https://www.deepcrawl.com/
Raven Tools: https://www.deepcrawl.com/
SEO PowerSuite: https://www.seopowersuite.com/
SearchMetrics Suite: https://www.seopowersuite.com/
Keyword Research Tools
Google Keyword Planner: https://adwords.google.com/KeywordPlannerMoz Keyword Explorer: https://moz.com/explorer
Keyword Tool: http://keywordtool.io/
Kwfinder: https://kwfinder.com/
Soovle:http://www.soovle.com/
SERPs KW Research: https://serps.com/tools/keyword-research/
UberSuggest: https://ubersuggest.io/
SEMrush: https://www.semrush.com
Answer The Public – Visual KW Research: http://answerthepublic.com/
Google Trends: https://trends.google.com/trends/
Google Correlate: https://www.google.com/trends/correlate/
Top Backlinks Checker Tools
Note that these all have their own metrics/ calculations, different size of indexes that’s why they offer results, different to each other.Ahrefs: https://ahrefs.com/
Small SEO Tools: http://smallseotools.com/backlink-checker/
Majestic SEO: https://majestic.com/
SEMrush: https://www.semrush.com/
Moz Open Site Explorer: https://moz.com/researchtools/ose/
Backlink Watch: http://www.backlinkwatch.com/
Rank Signals: https://www.ranksignals.com/
Caphyon: http://www.advancedlinkmanager.com/
Google Webmaster aka Search Console: https://www.google.com/webmasters/
Yahoo/Bing Webmaster: http://www.bing.com/toolbox/webmaster/
Open Link Profiler: http://www.openlinkprofiler.org/
SEO PowerSuite – WebMeUp: http://webmeup.com/
SEO Powersuite – SEO Spyglass: http://www.seo-spyglass.com/
Monitor Backlinks: https://monitorbacklinks.com/seo-tools/free-backlink-checker
SEO Chat Internal/External Link Analyzer: http://tools.seochat.com/tools/page-link-analyzer-seo/
Linkody: https://www.linkody.com/
Traffic Travis: https://www.traffictravis.com/
MoonSearch: http://www.moonsearch.com/
CognitiveSEO: https://explorer.cognitiveseo.com/
Kerboo: https://kerboo.com/solutions/backlink-analysis
Link Research Tools: http://www.linkresearchtools.com/index-2/
Google Link Operator: https://www.google.co.in/#q=link:mithileshjoshi.com+-site:mithileshjoshi.com
Search Metrics: https://suite.searchmetrics.com/en/research/links/backlink-analysis/
Alexa: http://www.alexa.com
Linkio: https://www.linkio.com/
Social Media Scheduling and Management
Hootsuite: http://www.hootsuite.com/BufferApp: http://www.bufferapp.com/
Social Oomph: https://www.socialoomph.com/
Hashtagify: http://hashtagify.me/
Friends+Me: https://friendsplus.me/
SproutSocial: http://sproutsocial.com/
CoSchedule: https://coschedule.com/
Twitter – TweetDeck: https://tweetdeck.twitter.com/
Social Media Count Tools
Shared Count: http://www.sharedcount.com/Varvy – Social Media Count Tool: https://varvy.com/tools/social/
Buzzswmo Chrome Extension: https://chrome.google.com/webstore/detail/buzzsumo
Duplicate Content Checker/Plagiarism Checker:
Copyscape: http://www.copyscape.com/Small SEO Tools – http://smallseotools.com/plagiarism-checker/
Dupli Checker: https://www.duplichecker.com/
Siteliner: http://www.siteliner.com/
Plag Spotter: http://www.plagspotter.com/
WebConfs – Similar Page Checker: http://www.webconfs.com/seo-tools/similar-page-checker/
Plagiarisma: http://plagiarisma.net/
Dupeoff: http://dupeoff.com/
CopyGator: http://www.copygator.com/
Hive Digital: https://www.hivedigital.com/free-tools/duplicate-content/
Plagium: http://www.plagium.com/
Article Checker: http://www.articlechecker.com/
Copyact: http://www.copyact.info.pl/
Dustball: http://www.dustball.com/cs/plagiarism.checker/
Paper Rater: http://www.paperrater.com/
Note: This is not the final list, still in progress. If you have any tool, please share in comments to make the list better and help others.
Good readers always drop comments!!