Ahrefs and Semrush are SEO automation tools. They both help rank your website on the top search engine page results (SERPs). Ahrefs is mainly used for SEO analysis. It gathers all vital information about backlinks while measuring website parameters and link quality.

It has a Site Explorer feature allows users to investigate organic traffic by monitoring keywords for which competitors are displayed. This allows users to see which websites are linking to sites in a specific industry. It helps you research new content ideas, check for content gaps, compare the content with competitors, and perform website audits.

Semrush is an SEO tool mainly used for keyword research, competitor analysis, and Google Ad optimization. It is used by many prominent brands, for example, Booking.com, Quora, HP, and eBay. It can quickly identify patterns and trends in your niche. It also allows you to assess your on-page SEO and determine the areas that require optimization for more lead generation.

It also helps you to compare to your competitors. It will also guide you in picking the keywords to target for organic search and Google ad campaigns.
Now let us understand the areas where they work better 

Keyword Research
Keyword research tools of both Ahrefs and Semrush are very similar. But Ahrefs has one advantage, which makes it a winner here. The keyword research feature in Ahrefs not only determines the difficulty of ranking for a given keyword but also tells you how many backlinks are required to rank on the first page of search results. This is missing in Semrush. 

Backlink Analysis
Ahrefs helps in analyzing the backlinks while Semrush helps in backlink database size, backlink reports and tools, and backlink auditing and building. This makes Semrush a winner here.

Competitor Analysis
Semrush’s competitor analysis tools are better than Ahref’s one. It provides more insight into competitors' activities and strategies.

Rank Tracking 
Again, this is a very crucial factor in understanding Ahrefs vs. Semrush. Ahrefs is a winner here as its SEO rank tracker tool provides more information than Semrush’s.

Site Audit
This feature is available in both Semrush and Ahrefs. Both of them offer a plethora of valuable recommendations. But Semrush is a winner here as its audit tool is much easier to use and can automatically generate a simple to-do list for you to follow. With  Ahrefs, you have to manually analyze your site audit reports to create the 'to-do' lists.

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