# crt.sh vs SurfaceDiff: side-by-side comparison (2026)

[crt.sh](https://cybersectools.com/tools/crt-sh) is a free [external attack surface management](https://cybersectools.com/categories/external-asm) solution. [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). 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

| | crt.sh | SurfaceDiff |
|---|---|---|
| Pricing model | Free | Commercial |
| Category | External Attack Surface Management | External Attack Surface Management |
| Verified | No | No |
| Deployment type | On-Premises | Cloud |
| Company size fit | Startup, SMB, Mid-Market, Enterprise | Startup, SMB, Mid-Market, Enterprise |
| Company | – | SurfaceDiff |
| Headquarters | – | – |

### Use cases and capabilities

| | crt.sh | SurfaceDiff |
|---|---|---|
| Subdomain Enumeration | Yes | Yes |
| Reconnaissance | Yes | Yes |
| Open Source | Yes | – |
| Bug Bounty | Yes | – |
| Enumeration | Yes | – |
| Network Reconnaissance | Yes | – |
| SSL | Yes | – |
| DNS Security | Yes | Yes |
| Security Scanning | Yes | Yes |
| Port Scanning | – | Yes |
| TLS | – | Yes |
| Network Scanning | – | Yes |
| Alerting | – | Yes |
| Visibility | – | Yes |
| Web Security | – | Yes |

### Core features

**crt.sh**

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

**SurfaceDiff**

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

### Integrations

**crt.sh**

1 integration listed. Sign in on the page to see them.

**SurfaceDiff**

No integrations listed.

## Which one fits you

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

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

## crt.sh vs SurfaceDiff FAQ

Common questions when comparing crt.sh vs SurfaceDiff for external attack surface management.

### What is the difference between crt.sh and SurfaceDiff?

**crt.sh**: Bash script for subdomain enumeration via crt.sh certificate transparency logs.

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

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

### Who makes crt.sh and SurfaceDiff?

**crt.sh** is open-source. **SurfaceDiff** is made by SurfaceDiff. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.

### Is crt.sh a good alternative to SurfaceDiff?

Often, yes. crt.sh and SurfaceDiff are both External Attack Surface Management products, and both cover DNS Security, Subdomain Enumeration, Security Scanning. Key differences: crt.sh is Free while SurfaceDiff is Commercial. Use the table above to see where features, deployment and company size fit differ.

## Related comparisons

- [crt.sh vs DDactic Attack Surface Discovery](https://cybersectools.com/compare/crt-sh-vs-ddactic-attack-surface-discovery)
- [crt.sh vs Attack Surface Scan](https://cybersectools.com/compare/attack-surface-scan-vs-crt-sh)
- [crt.sh vs MGM Security Partners recon me](https://cybersectools.com/compare/crt-sh-vs-mgm-security-partners-recon-me)
- [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 MGM Security Partners recon me](https://cybersectools.com/compare/mgm-security-partners-recon-me-vs-surfacediff)

## Alternatives to each

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

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Source: https://cybersectools.com/compare/crt-sh-vs-surfacediff

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More on crt.sh and SurfaceDiff: 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