Long before hashID became the modern go-to hash-detection utility, Hash-Identifier was one of the first widely used tools for figuring out what kind of hash you’re staring at. Written in Python, Hash-Identifier is a simple, interactive command-line tool that identifies the different types of hashes used to encrypt data, particularly passwords, by matching the input against a database of known hash patterns and lengths. It remains bundled in Kali Linux for its simplicity and speed, especially useful in quick CTF-style or beginner workflows.
This article covers Hash-Identifier’s design, installation, usage, real examples, and where it fits alongside newer tools like hashID.
What Is Hash-Identifier?
Hash-Identifier is a lightweight Python 2/3-compatible script that takes a hash string as input (either interactively or via a file) and returns a list of possible algorithms it could belong to, based on length and character-set analysis. Unlike hashID, it doesn’t map results directly to Hashcat modes or John formats, but its interactive prompt style makes it approachable for beginners learning about hash formats for the first time.
Architecture and Internal Working
- Interactive prompt: When launched without arguments, Hash-Identifier presents a banner and prompts the user to paste in a hash string directly.
- Length and charset analysis: The tool checks the hash’s total character length and whether it consists of hexadecimal characters, base64 characters, or other patterns.
- Pattern-matching database: An internal list of known algorithms and their typical hash lengths/structures (MD5, SHA-1, SHA-256, SHA-512, MySQL, Domain Cached Credentials, etc.) is compared against the input.
- Ranked output: Possible matches are printed, often with a rough indication of likelihood based on how distinctive the length/pattern is (e.g., a 32-character hex string could be MD5, MD4, NTLM, or several others, while a 40-character hex string is more distinctly SHA-1).
Installation
Hash-Identifier is included by default in Kali Linux. To install manually:
sudo apt update
sudo apt install hash-identifier -y
Verify installation:
hash-identifier
This launches the interactive prompt directly (there’s no --version flag in most builds).
Basic Usage
Hash-Identifier is primarily interactive rather than flag-driven. Launch it, then paste your hash when prompted:
hash-identifier
You’ll see a banner followed by:
HASH:
Paste your hash and press Enter.
Practical Command Examples
1. Identifying an MD5-style hash
$ hash-identifier
HASH: 5f4dcc3b5aa765d61d8327deb882cf99
Sample output:
Possible Hashs:
[+] MD5
[+] Domain Cached Credentials - MD4(MD4(($pass)).(strtolower($username)))
2. Identifying a SHA-1 hash
HASH: aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d
Sample output:
Possible Hashs:
[+] SHA-1
[+] MySQL5 - SHA-1(SHA-1(($pass)))
3. Identifying a SHA-256 hash
HASH: 5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d
Sample output:
Possible Hashs:
[+] SHA-256
[+] Haval-256
4. Piping a hash directly (non-interactive use in scripts)
echo "5f4dcc3b5aa765d61d8327deb882cf99" | hash-identifier
Real-World Use Cases (Authorized Lab Environments Only)
- CTF challenges: Quickly narrowing down a hash type when a challenge provides only a raw hash string with no further context.
- Beginner training labs: Introducing new security learners to the concept of hash algorithm structure and length-based identification before moving on to more advanced tools.
- Quick manual checks during authorized engagements: Confirming a hash’s likely type before invoking John the Ripper or Hashcat with the correct format/mode.
- Digital forensics triage: A fast first-pass check on an unknown hash value recovered from a file, config, or memory dump.
Workflow Integration
- Hash-Identifier → John the Ripper: Once a likely algorithm is identified, pass the corresponding
--formatvalue to John manually (Hash-Identifier doesn’t auto-map this, unlike hashID). - Hash-Identifier → Hashcat: Similarly, manually look up the corresponding
-mmode number in Hashcat’s mode reference once the algorithm is known. - Hash-Identifier alongside hashID: Many testers run both tools on ambiguous hashes and compare results, since their pattern databases and confidence heuristics differ slightly.
Performance Optimization
Hash-Identifier is a simple, near-instant identification tool with no meaningful performance considerations of its own. Its real value is in saving downstream cracking time by preventing testers from running John or Hashcat with an incorrect hash-format assumption.
Troubleshooting
| Issue | Cause | Fix |
|---|---|---|
| Tool exits immediately or throws Python errors | Python 2 vs Python 3 compatibility issue on some builds | Reinstall via apt, which ensures the correct interpreter is used, or check the Kali package changelog |
| Too many ambiguous matches | Hash length/charset shared by many algorithms (e.g., 32-char hex) | Use context (source system/application) to narrow down; cross-check with hashID |
| No matches for a hash | Unusual, salted, or non-standard format | Check for salt delimiters manually; try hashID’s extended mode for broader coverage |
Best Practices and Common Mistakes
- Don’t treat the first listed match as definitive — always consider the source system before choosing a cracking format.
- For salted or complex formats (e.g.,
$6$salt$hashUnix crypt), verify the delimiter structure manually since Hash-Identifier’s classic pattern matching can be less precise here than newer tools. - Combine with hashID for a second opinion on ambiguous hashes before committing to a lengthy cracking session.
- Use only for legitimate identification tasks — CTFs, authorized audits, or forensic investigations with proper authority.
FAQ
Is Hash-Identifier still maintained? It’s an older, largely stable tool; most activity in this space has shifted toward hashID, which has a larger and more actively maintained pattern database.
What’s the difference between Hash-Identifier and hashID? Hash-Identifier is interactive and simpler, without direct Hashcat/John format mapping. hashID is more modern, supports more hash types, and directly outputs the corresponding Hashcat mode and John format name.
Can Hash-Identifier crack passwords? No, it only identifies possible hash types. Actual cracking requires John the Ripper, Hashcat, or a similar dedicated tool.
Why did I get so many possible matches for one hash? Many algorithms produce hashes of identical length and character set (e.g., 32-character hex strings could be MD5, MD4, NTLM, and others), so context beyond the string itself is often needed to pin down the exact algorithm.
Summary
Hash-Identifier may be older and simpler than its successor hashID, but it remains a fast, no-frills way to get a first read on an unknown hash’s likely type — especially useful for beginners, CTF players, and quick manual checks during an engagement. Pairing it with a second identification pass from hashID, plus context about the hash’s source system, gives the most reliable starting point before committing real cracking time with John the Ripper or Hashcat.
References
- Kali Linux tool listing: https://www.kali.org/tools/hash-identifier/
- Hash-Identifier source (community mirrors): https://github.com/blackploit/hash-identifier
- hash-identifier man page:
man hash-identifier(available after installation)
