# SurfaceDiff vs tko-subs: side-by-side comparison (2026)

[SurfaceDiff](https://cybersectools.com/tools/surfacediff) is a commercial [external attack surface management](https://cybersectools.com/categories/external-asm) solution by [SurfaceDiff](https://cybersectools.com/companies/surfacediff). [tko-subs](https://cybersectools.com/tools/tko-subs) is a free [external attack surface management](https://cybersectools.com/categories/external-asm) solution. Features, integrations, deployment and the company behind each one, side by side.

Need the answer fast? [Best Attack Surface Management Solutions for Business](https://cybersectools.com/shortlists/best-attack-surface-solutions) picks Palo Alto Networks Cortex Xpanse, Microsoft Defender EASM, Mandiant Attack Surface Management and 4 more.

## Side-by-side comparison

| | SurfaceDiff | tko-subs |
|---|---|---|
| Pricing model | Commercial | Free |
| Category | External Attack Surface Management | External Attack Surface Management |
| Verified | No | No |
| Deployment type | Cloud | On-Premises |
| Company size fit | Startup, SMB, Mid-Market, Enterprise | Startup, SMB, Mid-Market, Enterprise |
| GitHub stars | – | 766 |
| Last commit | – | Jan 2021 |
| Company | SurfaceDiff | – |
| Headquarters | – | – |

### Use cases and capabilities

| | SurfaceDiff | tko-subs |
|---|---|---|
| DNS Security | Yes | – |
| Port Scanning | Yes | – |
| TLS | Yes | – |
| Subdomain Enumeration | Yes | Yes |
| Network Scanning | Yes | – |
| Security Scanning | Yes | – |
| Alerting | Yes | – |
| Reconnaissance | Yes | – |
| Visibility | Yes | – |
| Web Security | Yes | – |
| Security Research | – | Yes |

### Core features

**SurfaceDiff**

9 features listed. Sign in on the page to see them.

**tko-subs**

No features listed.

## Which one fits you

Based on what each listing shows: deployment, company size, price and open source.

- [SurfaceDiff](https://cybersectools.com/tools/surfacediff) fits if you want a cloud product.
- [tko-subs](https://cybersectools.com/tools/tko-subs) fits if you need to run it on your own servers, you need a free product and you want an open-source product.

## SurfaceDiff vs tko-subs FAQ

Common questions when comparing SurfaceDiff vs tko-subs for external attack surface management.

### What is the difference between SurfaceDiff and tko-subs?

**SurfaceDiff**: Continuous external attack surface monitoring that shows what changed between scans. Built by SurfaceDiff.

**tko-subs**: A tool for detecting and taking over subdomains with dead DNS records.

The table above shows where their features, integrations, deployment and company size fit differ.

### Who makes SurfaceDiff and tko-subs?

**SurfaceDiff** is made by SurfaceDiff. **tko-subs** is open-source with 766 GitHub stars. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.

### Is SurfaceDiff a good alternative to tko-subs?

Often, yes. SurfaceDiff and tko-subs are both External Attack Surface Management products, and both cover Subdomain Enumeration. Key differences: SurfaceDiff is Commercial while tko-subs is Free, tko-subs is open-source. Use the table above to see where features, deployment and company size fit differ.

## Related comparisons

- [SurfaceDiff vs DDactic Attack Surface Discovery](https://cybersectools.com/compare/ddactic-attack-surface-discovery-vs-surfacediff)
- [SurfaceDiff vs Attack Surface Scan](https://cybersectools.com/compare/attack-surface-scan-vs-surfacediff)
- [SurfaceDiff vs Trickest ASM - Attack Surface Management](https://cybersectools.com/compare/surfacediff-vs-trickest-asm-attack-surface-management)
- [tko-subs vs DDactic Attack Surface Discovery](https://cybersectools.com/compare/ddactic-attack-surface-discovery-vs-tko-subs)
- [tko-subs vs Attack Surface Scan](https://cybersectools.com/compare/attack-surface-scan-vs-tko-subs)
- [tko-subs vs Trickest ASM - Attack Surface Management](https://cybersectools.com/compare/tko-subs-vs-trickest-asm-attack-surface-management)

## Alternatives to each

- [See all SurfaceDiff alternatives](https://cybersectools.com/alternatives/surfacediff)
- [See all tko-subs alternatives](https://cybersectools.com/alternatives/tko-subs)

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Source: https://cybersectools.com/compare/surfacediff-vs-tko-subs

For AI agents: each product above has its own Markdown page (add .md to its URL, for example https://cybersectools.com/tools/surfacediff.md). Every CybersecTools shortlist is listed at https://cybersectools.com/shortlists.md.

More on SurfaceDiff and tko-subs: funding, momentum, hiring and news, plus the full product and company record, are available through the Mandos MCP Server (paid plans), which connects to AI assistants: https://mandos.io/mcp?utm_source=cybersectools.com&utm_medium=compare-md