# GreyNoise Block vs Unit221B eWitness: side-by-side comparison (2026)

[GreyNoise Block](https://cybersectools.com/tools/greynoise-block) is a commercial [threat intel platforms](https://cybersectools.com/categories/tip) solution by [GreyNoise, Inc](https://cybersectools.com/companies/greynoise-inc). [Unit221B eWitness](https://cybersectools.com/tools/unit221b-ewitness) is a commercial [threat intel platforms](https://cybersectools.com/categories/tip) solution by [Unit 221B](https://cybersectools.com/companies/unit-221b). Features, integrations, deployment and the company behind each one, side by side.

Need the answer fast? [Best Threat Intelligence Platform Solutions for Business](https://cybersectools.com/shortlists/best-threat-intelligence-platforms) picks Recorded Future Threat Intelligence, Google Threat Intelligence, CrowdStrike Falcon Adversary Intelligence and 4 more.

## Side-by-side comparison

| | GreyNoise Block | Unit221B eWitness |
|---|---|---|
| Pricing model | Commercial | Commercial |
| Category | Threat Intel Platforms | Threat Intel Platforms |
| Verified | No | No |
| Deployment type | Cloud | Cloud |
| Company size fit | SMB, Mid-Market, Enterprise | Enterprise, Mid-Market |
| Company | GreyNoise, Inc. | Unit 221B |
| Headquarters | – | – |

### Use cases and capabilities

| | GreyNoise Block | Unit221B eWitness |
|---|---|---|
| Attack Detection | Yes | – |
| IP Lookup | Yes | – |
| Vulnerability Exploitation | Yes | – |
| Cyber Threat Intelligence | Yes | Yes |
| Threat Research | – | Yes |
| Security Research | – | Yes |
| Investigation | – | Yes |
| Dark Web Monitoring | – | Yes |
| Threat Feed | – | Yes |

### Core features

**GreyNoise Block**

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

**Unit221B eWitness**

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

### Integrations

**GreyNoise Block**

2 integrations listed. Sign in on the page to see them.

**Unit221B eWitness**

No integrations listed.

## Which one fits you

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

- [GreyNoise Block](https://cybersectools.com/tools/greynoise-block) fits if you are a small business.

## GreyNoise Block vs Unit221B eWitness FAQ

Common questions when comparing GreyNoise Block vs Unit221B eWitness for threat intel platforms.

### What is the difference between GreyNoise Block and Unit221B eWitness?

**GreyNoise Block**: Real-time threat intel platform detecting malicious scanning & exploitation. Built by GreyNoise, Inc.

**Unit221B eWitness**: Threat intel platform for discovering cybercrime on encrypted chat networks. Built by Unit 221B.

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

### Who makes GreyNoise Block and Unit221B eWitness?

**GreyNoise Block** is made by GreyNoise, Inc. **Unit221B eWitness** is made by Unit 221B. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.

### Is GreyNoise Block a good alternative to Unit221B eWitness?

Often, yes. GreyNoise Block and Unit221B eWitness are both Threat Intel Platforms products, and both cover Cyber Threat Intelligence. Use the table above to see where features, deployment and company size fit differ.

## Related comparisons

- [GreyNoise Block vs Validin](https://cybersectools.com/compare/greynoise-block-vs-validin)
- [GreyNoise Block vs Cypho](https://cybersectools.com/compare/cypho-vs-greynoise-block)
- [GreyNoise Block vs Ninja Signal](https://cybersectools.com/compare/greynoise-block-vs-ninja-signal)
- [Unit221B eWitness vs Validin](https://cybersectools.com/compare/unit221b-ewitness-vs-validin)
- [Unit221B eWitness vs Cypho](https://cybersectools.com/compare/cypho-vs-unit221b-ewitness)
- [Unit221B eWitness vs Ninja Signal](https://cybersectools.com/compare/ninja-signal-vs-unit221b-ewitness)

## Alternatives to each

- [See all GreyNoise Block alternatives](https://cybersectools.com/alternatives/greynoise-block)
- [See all Unit221B eWitness alternatives](https://cybersectools.com/alternatives/unit221b-ewitness)

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Source: https://cybersectools.com/compare/greynoise-block-vs-unit221b-ewitness

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

More on GreyNoise Block and Unit221B eWitness: 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