Semrush vs Similarweb for competitor traffic:

Semrush vs Similarweb for competitor traffic:
I checked the same 10 competitor domains against sites where I knew the real numbers.

Semrush
➕ Organic traffic estimate ties directly to keyword + position data
➕ Best when most of the competitor's traffic is search
➖ Blind to direct/social/referral — under-counts brand-heavy sites

Similarweb
➕ Full traffic mix (direct, social, referral, paid), not just organic
➕ Closer on big brand sites where direct dominates
➖ Noisy on small sites; my known-truth site was 2x off under 50k visits

Best for: organic-share analysis → Semrush. Total-traffic + channel mix → Similarweb.

Price-vs-value: Semrush was within ~20% on search-driven competitors; Similarweb won on brand-heavy ones but flailed on small sites. Match the tool to the competitor's traffic shape.

Pick Semrush for search-led niches. Skip Similarweb for sub-50k-visit competitors — the noise is real.

Tested against numbers I actually know.