Unlocking Hashcat’s Full Potential: How GPU Optimization Reduced Cracking Time by 85% — A Wordlist Benchmark Breakdown

Digi
2 min readOct 9, 2024

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After optimizing Hashcat to recognize my NVIDIA RTX 4080 Super GPU as the default device and applying the two recommended modes (-w 4 and -O), I reduced the time to process an 8.4 billion password wordlist from 2 days to just 25 minutes compared to the default settings.

This writeup follows my previous Hashcat optimization guide, “A Complete Guide to Optimizing Hashcat: Use Your GPU Instead of CPU for 60–90% Faster Cracking”.

Wordlists

Wordlists

Every cybersecurity student or analyst is familiar with the go-to wordlist, RockYou.txt. In this writeup, I will be focusing on RockYou.txt, along with Crackstation.txt and RockYou2021.txt. Here are the stats of the three wordlists.

For all the Hashcat benchmarks, I am using an NVIDIA RTX 4080 Super Founders Edition (GPU) alongside an AMD Threadripper 3960X (CPU). To gather more comprehensive data, I tested with 3 hashes instead of just 1. The hash mode used is 500 (md5crypt) on Hashcat.

RockYou.txt

File size: 139.92 MB
Number of lines: 14.3M passwords
CPU time: 4 minutes, 10 seconds
GPU time: 34 seconds.

Crackstation.txt

File size: 15 GB
Number of lines: 1.5B passwords
CPU time: 8 hours, 37 minutes
GPU time: 48 minutes

RockYou2021.txt

File size: 100 GB
Number of lines: 8.4B passwords
CPU time: 2 days, 1 hour
GPU time: 2 hours, 47 minutes

The above benchmarks compare CPU time, where only my CPU was used with no optimization, to GPU time, where my GPU was utilized with the optimized settings (-w 4 and -O).

Here is a complete breakdown with and without optimization:

RockYou.txt

No optimization:

  • CPU: 4 mins 35 secs

With optimization:

  • 34 seconds without using (-O)
  • 13 seconds with using (-O)

62% faster

  • 9 seconds with (-O -w 4)

74% faster

Crackstation.net

No optimization:

  • CPU: 8 hours, 37 minutes

With optimization:

  • 48 minutes without (-O)
  • 7 minutes, 40 seconds with (-O)

84% faster

  • 4 minutes, 10 seconds with (-O -w 4)

91% faster

Rockyou2021

No optimization:

  • CPU: 2 days, 1 hour

With optimization:

  • 2 hours 47 minutes without (-O)
  • 35 minutes with (-O)

79% faster

  • 25 minutes with (-O -w 4)

85% faster

If you’re interested in learning how to optimize Hashcat, check out my previous writeup, “A Complete Guide to Optimizing Hashcat: Use Your GPU Instead of CPU for 60–90% Faster Cracking”.

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Digi
Digi

Written by Digi

Cybersecurity professional with 20+ years of experience as a PHP web developer and Linux server administrator. Enjoys CTF events to expand knowledge.

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