Amass vs SurfaceDiff: Side-by-Side Comparison (2026)

Amass: Amass is an open-source OWASP tool for comprehensive attack surface mapping and asset discovery through domain reconnaissance and subdomain enumeration..

SurfaceDiff: Continuous external attack surface monitoring that shows what changed between scans. built by SurfaceDiff. Core capabilities include Domain baseline scan for publicly exposed assets, Subdomain discovery, DNS record enumeration..

Both serve the External Attack Surface Management market but differ in approach, feature depth, and target audience.

Amass is open-source with 14,260 GitHub stars. SurfaceDiff is developed by SurfaceDiff. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.

Amass and SurfaceDiff serve similar External Attack Surface Management use cases: both are External Attack Surface Management tools, both cover DNS Security, Subdomain Enumeration, Reconnaissance. Key differences: Amass is Free while SurfaceDiff is Commercial, Amass is open-source. Review the feature comparison above to determine which fits your requirements.