# Krakatau

Krakatau is a Malware Analysis product. It runs on-premises. Pricing is free.

A Java bytecode assembler and disassembler toolkit that converts classfiles to human-readable format and provides decompilation capabilities for reverse engineering Java applications.

Checked October 2026.

## What is Krakatau?

Krakatau is a Java bytecode analysis toolkit that provides assembler and disassembler capabilities for Java classfiles.

The tool converts binary Java classfiles into human-readable text format, enabling analysts to examine the low-level structure and implementation details of Java applications. It supports the creation of new classfiles from scratch by allowing users to write bytecode manually in text format.

Krakatau includes decompilation functionality that converts Java binaries back to readable source code, making it useful for reverse engineering Java applications. The tool can handle highly obfuscated code and supports some undocumented JVM features found in older versions.

The disassembler output allows for detailed examination and comparison of Java binaries at the bytecode level. This capability is particularly valuable for malware analysis, security research, and understanding the inner workings of Java applications.

The tool has limitations with newer Java features, specifically lacking support for Java 8+ constructs such as lambda expressions. It focuses primarily on traditional Java bytecode structures and older JVM implementations.

Tags: Reverse Engineering, Binary Analysis, Security Research, Obfuscation

## Where it fits in your security program (NIST CSF 2.0)

- [Respond](https://cybersectools.com/guides/building-respond-program-small-team): helps you contain and handle incidents.

## Quick facts

- Category: [Security Operations](https://cybersectools.com/categories/security-operations) · [Malware Analysis](https://cybersectools.com/categories/malware-analysis)
- Deployment: On-Premises
- Company size fit: Startup, SMB, Mid-Market, Enterprise
- Pricing model: Free
- GitHub stars: 2,188
- Website: github.com

## Where it ranks

No shortlist covers this product's category yet. The closest is [Best MDR Solutions for Business](https://cybersectools.com/shortlists/best-mdr-solutions).

## Krakatau FAQ

### What is Krakatau?

Krakatau is a product in the Malware Analysis category. It covers Reverse Engineering, Binary Analysis and Security Research.

### What is the pricing for Krakatau?

Krakatau is free. Download and setup instructions are at https://github.com/Storyyeller/Krakatau/.

### What are alternatives to Krakatau?

Alternatives to Krakatau listed on CybersecTools:

1. [CodeHunter Labs](https://cybersectools.com/tools/codehunter-labs) - Research division powering CodeHunter's pre-execution malware detection engine. (Commercial)
2. [Zenyard RE Agent](https://cybersectools.com/tools/zenyard-re-agent) - AI agent for in-depth binary analysis and reverse engineering assistance. (Commercial)
3. [Nightwing DejaVM](https://cybersectools.com/tools/nightwing-dejavm) - Whole-system emulation environment for software dev, debugging, testing & security (Commercial)
4. [Joe Security Joe Reverser](https://cybersectools.com/tools/joe-security-joe-reverser) - Agentic AI tool for automated malware reverse engineering & phishing analysis. (Commercial)
5. [Reverse Engineering & Malware Analysis](https://cybersectools.com/tools/reverse-engineering-and-malware-analysis) - Malware analysis & reverse engineering service producing IOCs, YARA/Sigma rules. (Commercial)

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

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

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

## Compare Krakatau with similar solutions

- [Krakatau vs CodeHunter Labs](https://cybersectools.com/compare/codehunter-labs-vs-krakatau)
- [Krakatau vs Zenyard RE Agent](https://cybersectools.com/compare/krakatau-vs-zenyard-re-agent)
- [Krakatau vs Nightwing DejaVM](https://cybersectools.com/compare/krakatau-vs-nightwing-dejavm)

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

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

For AI agents: every CybersecTools shortlist is listed at https://cybersectools.com/shortlists.md, and any compare page has a Markdown copy too (add .md to its URL).

More on Krakatau: 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