Moz vs Majestic vs Ahrefs vs SEMrush

Backlinks/Inbound links are the most important part of Google’s algorithm. But which of Moz (£63.25 to £382.70 per month), Majestic (£29.99 to £250.00 per month), Ahrefs (£50.52 to £829.93 per month) or SEMrush (£44.73 to £351.36 per month) offer the most complete data? Which offers the best value?

*Please note that this in an impartial revenue & I do not earn any income from any of the vendors listed below.The options for SEO link indexing services are as follows (from cheapest entry level option to most expensive entry level option):

Majestic SEO

Around since 2004. Entry level price is £29.99 per month. Unique URLs crawled: 836,841,259,212 (836 billion). 70,700 visitors per day to the Majestic website.

I view Majestic SEO as the big daddy of link indexes perfect for hardcore link building & analysis. They offer various pricing options making it attainable for small businesses all the way through to enterprise level. This is a specific link building/link indexation software tool – no rank checkers or other add ons are generally offered but for core link building & indexation it doesn’t get any better than this at this time.

Rating: 8/10

SEMrush

Around since: 2008. Entry level price is £44.73 per month. 338,000 visitors to the SEMrush domain per day. Claimed 627,378 users.

This tool is a better rank checker than an indexation utility in my opinion. The data on wider data sets is simply hit & miss & I’d only use this tool on projects with smaller data sets. Given that its best use is in aiding keyword research – which I already have the Google Adwords Keyword Planner for – I think a 5/10 possibly verges on the charitable.

Rating: 5/10

Ahrefs

Around since 2011. Entry level pricing starts at £50.52 per month. 208,000 visitors per day to the domain.

Ahrefs updates every 30 minutes giving it an immediate jump on the rest of the field. The software has decent utility for competitor comparison. You are also able to segment inbound links by type (text, image, nofollow, etc.) By trying to include utilities such as a rank checker & a monetization of traffic component I feel the software loses its focus somewhat. However, overall, its a solid entrant into the link indexation market & you could do a lot worse. Price is not cheap but reasonable value for money.

Rating: 7/10

Moz Pro

Around since 2008 as software developers. Entry level price is £63.25 per month. 248,000 visitors per day to the site itself. Expensive for what it is – a jack of all trades, master of none kind of link index which is fairly detailed but not broad & inclusive enough.

The On Page Optimization Tool is good for complete SEO novices. Its formulaic approach to SEO, though is somewhat misleading for anything more than ‘gaping whole error’ SEO changes. The Social Media Monitoring Tool is often found to be only partially accurate which begs the question – why offer it if you can’t deliver accurate information? For the most part Moz is solid if unspectacular – you will get a consistently partial view of the assumed Google index & less sophisticated but good ‘broad strokes’ metrics & comparison tools. A reasonable choice for novice SEO’s but hardly cheap.

Rating: 6/10

Number of linking root domains are key and an easy way to determine the expansiveness of a given link metric service. There is no full representation of the Internet, every link service, is thus a biased sample of the internet.

CNN.com was run through all 4 major link services:

Majestic SEO (historic) claim 1,231,281 linking root domains.

Ahrefs claim 402,000 domains link to the website. They offer very limited free crawls per week/month.

Majestic SEO (fresh) claim 380,286 linking root domains.

SEMrush claim 296,000 domains link to the website.

Moz claims 58,465 Linking Root Domains.

Head to Head Competitor Comparison on Same Link Checker

Skysports.com was then also run through Ahrefs:

Ahrefs claim 16,287 domains link to the website 12,038,604 times from 12,968 Referring IPs. 84 of these links were from .edu or .ac.uk (and similar) websites. 11,627,431 or 97% of the links were dofollow – with 372,194 being nofollow. The website does around 266,000 visitors per day according to a (different) traffic estimator.

Talksport.com by way of comparison:

Ahrefs list 5,105 Referring Domains sending a grand total of 619,401 inbound links from 4,533 Referring IPs. 10 of these links were from .edu or .ac.uk (and similar) websites. A relatively small 81% (500,487) of total links were dofollow in nature. According to independent (different) traffic estimation the website gets around 34,000 visitors per day.

Google doesn’t give too much information about inbound link metrics. All we have to go on is the Google Search ConsoleMoz offers better data than Ahrefs generally speaking.

Each service has to invent its own crawl prioritization. None will ever be an exact match for Google but based what I’ve discovered no single one is vastly superior to the rest. When you find billions of links, you have to decide which to crawl next. Google has a crawl prioritization, as due all the various link services. If you want to build a the biggest index possible, you prioritize crawling pages on websites that are known to throw up new links on a regular basis.
Open Site Explorer is a useful but limited tool given the above information. They claim an Index of  407 Billion URLs & 2 Trillion Links.

Majestic Historic offers by far the widest data out there. SEMrush are getting better but still lag behind for the time being.

Moz, Majestic, Ahrefs & SEMrush seek to mimic Google. Having the most Google-like data is clearly the goal.

Other link checker tools include:

Raven Tools

SEO Spyglass

Screaming Frog

Webmaster Tools

Other useful SEO related tools

Google Trends

CopyScape

SpyFu

GTmetrix

Wayback Machine

Google Keyword Planner

Chrome Developer Tools

Xenu Link Sleuth

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