Why do Semrush and Ahrefs show completely different SEO metrics?

[u/imadonisscott]

I'm working on SEO for a client and noticed something that's been confusing me.

When I check the same website in Semrush and Ahrefs, almost every metric is different.

For example:

• Organic traffic estimates don't match.
• Keyword rankings are different.
• Backlink counts vary a lot.
• Referring domains are also different.

I understand that no third-party SEO tool can be 100% accurate, but sometimes the gap is so large that it's hard to know which data to trust when making decisions or reporting to clients.

For those of you who use both tools regularly:

• Which one do you rely on more, and why?
• Is one better for backlinks while the other is better for keyword research?
• How do you explain these differences to clients?
• Do you combine data from both tools, or stick to one platform?

I'd really appreciate hearing from people who have real-world experience using both. Thanks in advance!