# rsatool

rsatool is a Penetration Testing product. It runs on-premises. Pricing is free.

A Python utility that calculates RSA cryptographic parameters and generates OpenSSL-compatible private keys from prime numbers or modulus/exponent pairs.

Checked October 2026.

## What is rsatool?

rsatool is a Python-based utility that calculates RSA cryptographic parameters including p, q, n, d, e values and RSA-CRT parameters (dP, dQ, qInv).

The tool accepts input in two formats: either two prime numbers (p, q) or a modulus and private exponent (n, d). It then computes the remaining RSA parameters needed for cryptographic operations.

Key features include:
- Calculation of standard RSA parameters (p, q, n, d, e)
- Generation of RSA-CRT parameters (dP, dQ, qInv)
- Display of calculated parameters in readable format
- Export functionality for OpenSSL-compatible private keys
- Support for both DER and PEM encoding formats
- Command-line interface for easy integration

The tool requires Python 3.7 or higher and depends on the pyasn1 and gmpy2 libraries for ASN.1 encoding and mathematical operations respectively.

Output can be saved to files in industry-standard formats, making it compatible with OpenSSL and other cryptographic tools that work with RSA private keys.

Tags: Security Tools

## Quick facts

- Category: [Offensive Security](https://cybersectools.com/categories/offensive-security-testing) · [Penetration Testing](https://cybersectools.com/categories/pentesting-tools)
- Deployment: On-Premises
- Company size fit: Startup, SMB, Mid-Market, Enterprise
- Pricing model: Free
- GitHub stars: 1,568
- Website: github.com

## rsatool FAQ

### What is rsatool?

rsatool is a product in the Penetration Testing category. It covers Security Tools.

### What is the pricing for rsatool?

rsatool is free. Download and setup instructions are at https://github.com/ius/rsatool/.

### What are alternatives to rsatool?

Alternatives to rsatool listed on CybersecTools:

1. [Managed Autonomous Pentesting (MAP)](https://cybersectools.com/tools/hackurity-art-stack) - Managed continuous autonomous pentesting using payload-less exploitation and attack paths (Commercial)
2. [XBOW Captcha Bypass Tool](https://cybersectools.com/tools/xbow-captcha-bypass-tool) - AI-powered automated penetration testing platform for vulnerability discovery (Commercial)
3. [Burp Suite Professional](https://cybersectools.com/tools/burp-suite-professional) - A web application security testing platform that combines manual and automated testing tools for conducting comprehensive security assessments and penetration testing. (Commercial)
4. [FireCompass AI-powered Pen Testing](https://cybersectools.com/tools/firecompass-ai-powered-pen-testing) - AI-powered automated pen testing & continuous red teaming platform (Commercial)
5. [ImmuniWeb® On-Demand](https://cybersectools.com/tools/immuniwebr-on-demand) - ImmuniWeb® On-Demand is a web application penetration testing platform that combines AI-powered automation with manual security testing to provide comprehensive vulnerability assessments and compliance reporting. (Commercial)

Compare all rsatool alternatives at [https://cybersectools.com/alternatives/rsatool](https://cybersectools.com/alternatives/rsatool)

### What deployment and organization size does rsatool fit?

rsatool is available as on-premises software. It is listed for startups, small businesses, mid-market companies and enterprises. It is free.

## Compare rsatool with similar solutions

- [rsatool vs Managed Autonomous Pentesting (MAP)](https://cybersectools.com/compare/hackurity-art-stack-vs-rsatool)
- [rsatool vs XBOW Captcha Bypass Tool](https://cybersectools.com/compare/rsatool-vs-xbow-captcha-bypass-tool)
- [rsatool vs Burp Suite Professional](https://cybersectools.com/compare/burp-suite-professional-vs-rsatool)

All alternatives to rsatool: [/alternatives/rsatool](https://cybersectools.com/alternatives/rsatool)

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Source: https://cybersectools.com/tools/rsatool

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More on rsatool: 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=product-md