K-Quantization and its Impact on Output Performance
Pith reviewed 2026-05-20 05:33 UTC · model grok-4.3
The pith
Quantization from 8-bit to 2-bit reduces LLM performance on reasoning and comprehension tasks, with larger models showing greater resilience and mid-sized models offering the best efficiency balance.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The authors establish that performance improves with higher bit precision such as 8-bit Q8_0, albeit with diminishing returns, while aggressive quantization such as 2-bit Q2_K usually retains acceptable accuracy across most models and tasks, though larger models demonstrate greater resilience to precision loss and mid-sized models in the 7-9 billion parameter range strike an optimal balance between efficiency and resource usage.
What carries the argument
Evaluation of eight LLMs at discrete quantization levels from Q2_K to Q8_0 on MMLU-Pro, CRUXEval, and MuSR to track accuracy as bit precision decreases.
Load-bearing premise
The chosen benchmarks and the specific eight LLMs tested are representative enough to support general statements about quantization impacts across models and tasks.
What would settle it
Repeating the tests on a fresh collection of models or benchmarks and observing that mid-sized models no longer provide the best efficiency-performance trade-off or that all models lose accuracy equally at 2 bits would undermine the reported trends.
Figures
read the original abstract
Recent advancements in large language models (LLMs) have shown their remarkable capacities in many NLP tasks. However, their substantial size often presents challenges for deployment. This necessitates efficient techniques for model compression, with quantization emerging as a prominent solution. Despite its benefits, the exact impact of quantization (from 2- to 6-bit) on the performance and accuracy of LLMs remains an active area of research. This paper investigates the performance of eight LLMs at various quantization levels, focusing on tasks such as MMLU-Pro for knowledge processing and reasoning, CRUXEval for code comprehension, and MuSR for reading comprehension. Our results show a consistent trend where higher precision (e.g., 8-bit Q8\_0) yields improved performance, albeit with diminishing returns. Aggressive quantization (e.g., 2-bit Q2\_K) usually retains acceptable accuracy, though some models show a substantial loss in performance. Our findings indicate that while lower bit precision generally reduces performance, the impact varies across models and tasks. Larger models show greater resilience to aggressive quantization, but can still undergo significant drops at lower precision levels. Mid-sized models in the 7-9 billion parameter range strike an optimal balance between efficiency and resource usage. Such results provide insights into the trade-offs between model size, quantization, and performance.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper presents an empirical study on the effects of quantization levels (specifically K-quantization from 2-bit to 8-bit) on the performance of eight large language models across three benchmarks: MMLU-Pro, CRUXEval, and MuSR. The authors observe that higher precision generally leads to better performance with diminishing returns, that 2-bit quantization often preserves acceptable accuracy, that larger models are more resilient to aggressive quantization, and that models in the 7-9 billion parameter range offer an optimal trade-off between efficiency and performance.
Significance. Should the trends prove robust, the results offer valuable practical insights for selecting quantization strategies and model sizes for efficient LLM deployment. The direct measurement approach avoids circularity and provides falsifiable observations on quantization impacts.
major comments (2)
- Abstract: The general claims about larger models showing greater resilience to aggressive quantization and mid-sized (7-9B) models striking an optimal balance rest on a sample of only eight LLMs and three benchmarks. The manuscript provides no justification for model or benchmark selection, no sensitivity analysis, and no additional models to test generalizability, which is load-bearing for the broad statements on quantization impacts.
- Abstract: The reported trends lack any mention of experimental controls, statistical tests, error bars, run-to-run variance, or exact model identities and architectures, making it impossible to verify the degree to which the data support the stated performance claims.
minor comments (1)
- Abstract: The title uses the term 'K-Quantization' without definition or explanation of what 'K' denotes, which could be clarified for readers unfamiliar with the specific quantization scheme.
Simulated Author's Rebuttal
We thank the referee for their constructive feedback, which highlights important areas for improving the clarity and robustness of our empirical study. We address each major comment point by point below, indicating planned revisions to the manuscript.
read point-by-point responses
-
Referee: Abstract: The general claims about larger models showing greater resilience to aggressive quantization and mid-sized (7-9B) models striking an optimal balance rest on a sample of only eight LLMs and three benchmarks. The manuscript provides no justification for model or benchmark selection, no sensitivity analysis, and no additional models to test generalizability, which is load-bearing for the broad statements on quantization impacts.
Authors: We acknowledge that the observed trends are derived from eight models and three benchmarks, and that the abstract does not explicitly justify these choices. In the revised manuscript we will add a methodology subsection detailing the rationale for model selection (to span a representative range of sizes and families) and benchmark selection (standard tasks covering knowledge, code, and reasoning). We will also insert a limitations paragraph noting the sample size and calling for future work with additional models and sensitivity checks. These additions provide necessary context without overclaiming generalizability. revision: yes
-
Referee: Abstract: The reported trends lack any mention of experimental controls, statistical tests, error bars, run-to-run variance, or exact model identities and architectures, making it impossible to verify the degree to which the data support the stated performance claims.
Authors: We agree that greater experimental transparency is required. The revised version will expand the experimental setup to list exact model identities and architectures, describe quantization parameters and any reproducibility controls (e.g., fixed random seeds), and clarify that the quantization process itself is deterministic once parameters are set. Where multiple evaluation runs exist we will report variance or error bars; otherwise we will explicitly note the deterministic nature and any single-run limitations. These details will be added to both the main text and abstract where space permits. revision: yes
Circularity Check
No circularity: direct empirical reporting of quantization effects
full rationale
The paper conducts and reports direct experimental measurements of eight LLMs across quantization levels on three fixed benchmarks (MMLU-Pro, CRUXEval, MuSR). No derivation chain, fitted parameters, equations, or predictions exist; claims consist of observed trends and comparisons from the collected data. No self-citations, ansatzes, or renamings reduce any result to its own inputs by construction. The analysis is self-contained against external benchmarks and therefore exhibits no circularity.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption Benchmark scores on MMLU-Pro, CRUXEval, and MuSR reflect meaningful differences in model capability under quantization.
Reference graph
Works this paper leans on
-
[1]
Wei, Jason and Wang, Xuezhi and Schuurmans, Dale and Bosma, Maarten and Ichter, Brian and Xia, Fei and Chi, Ed H. and Le, Quoc V. and Zhou, Denny , title =. Proceedings of the 36th International Conference on Neural Information Processing Systems , articleno =. 2022 , isbn =
work page 2022
-
[2]
AWQ: Activation-aware Weight Quantization for On-Device LLM Compression and Acceleration
Lin, Ji and Tang, Jiaming and Tang, Haotian and Yang, Shang and Xiao, Guangxuan and Han, Song , title =. GetMobile: Mobile Comp. and Comm. , month = jan, pages =. 2025 , issue_date =. doi:10.1145/3714983.3714987 , abstract =
-
[3]
``Give Me BF 16 or Give Me Death''? Accuracy-Performance Trade-Offs in LLM Quantization
Kurtic, Eldar and Marques, Alexandre Noll and Pandit, Shubhra and Kurtz, Mark and Alistarh, Dan. ``Give Me BF 16 or Give Me Death''? Accuracy-Performance Trade-Offs in LLM Quantization. Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers). 2025. doi:10.18653/v1/2025.acl-long.1304
-
[4]
Proceedings of the Thirty-Fourth International Joint Conference on Artificial Intelligence,
Exploring the Trade-Offs: Quantization Methods, Task Difficulty, and Model Size in Large Language Models From Edge to Giant , author =. Proceedings of the Thirty-Fourth International Joint Conference on Artificial Intelligence,. 2025 , month =. doi:10.24963/ijcai.2025/902 , url =
-
[5]
The Twelfth International Conference on Learning Representations,
Tim Dettmers and Ruslan Svirschevski and Vage Egiazarian and Denis Kuznedelev and Elias Frantar and Saleh Ashkboos and Alexander Borzunov and Torsten Hoefler and Dan Alistarh , title =. The Twelfth International Conference on Learning Representations,. 2024 , url =
work page 2024
-
[6]
int8 (): 8-bit matrix multiplication for transformers at scale , author=
Gpt3. int8 (): 8-bit matrix multiplication for transformers at scale , author=. Advances in neural information processing systems , volume=
-
[7]
S. M. Towhidul Islam Tonmoy and S. M. Mehedi Zaman and Vinija Jain and Anku Rani and Vipula Rawte and Aman Chadha and Amitava Das , title =. CoRR , volume =. 2024 , url =. doi:10.48550/ARXIV.2401.01313 , eprinttype =. 2401.01313 , timestamp =
work page internal anchor Pith review Pith/arXiv arXiv doi:10.48550/arxiv.2401.01313 2024
-
[8]
Language Models are Few-Shot Learners , url =
Brown, Tom and Mann, Benjamin and Ryder, Nick and Subbiah, Melanie and Kaplan, Jared D and Dhariwal, Prafulla and Neelakantan, Arvind and Shyam, Pranav and Sastry, Girish and Askell, Amanda and Agarwal, Sandhini and Herbert-Voss, Ariel and Krueger, Gretchen and Henighan, Tom and Child, Rewon and Ramesh, Aditya and Ziegler, Daniel and Wu, Jeffrey and Winte...
-
[9]
GPTQ: Accurate Post-Training Quantization for Generative Pre-trained Transformers
Elias Frantar and Saleh Ashkboos and Torsten Hoefler and Dan Alistarh , title =. CoRR , volume =. 2022 , url =. doi:10.48550/ARXIV.2210.17323 , eprinttype =. 2210.17323 , timestamp =
work page internal anchor Pith review Pith/arXiv arXiv doi:10.48550/arxiv.2210.17323 2022
-
[10]
Forty-first International Conference on Machine Learning,
Wei Huang and Yangdong Liu and Haotong Qin and Ying Li and Shiming Zhang and Xianglong Liu and Michele Magno and Xiaojuan Qi , title =. Forty-first International Conference on Machine Learning,. 2024 , url =
work page 2024
-
[11]
Mahoney and Kurt Keutzer , title =
Sehoon Kim and Coleman Hooper and Amir Gholami and Zhen Dong and Xiuyu Li and Sheng Shen and Michael W. Mahoney and Kurt Keutzer , title =. Forty-first International Conference on Machine Learning,. 2024 , url =
work page 2024
-
[12]
Floating-point arithmetic --- Wikipedia , The Free Encyclopedia
Wikipedia contributors. Floating-point arithmetic --- Wikipedia , The Free Encyclopedia. 2024
work page 2024
-
[13]
Google. The bfloat16 numerical format. The BFLOAT16 Numerical Format , publisher=
-
[14]
Lower perplexity is not always human-like
Tatsuki Kuribayashi and Yohei Oseki and Takumi Ito and Ryo Yoshida and Masayuki Asahara and Kentaro Inui , editor =. Lower Perplexity is Not Always Human-Like , booktitle =. 2021 , url =. doi:10.18653/V1/2021.ACL-LONG.405 , timestamp =
-
[15]
Gu, Alex and Roziere, Baptiste and Leather, Hugh James and Solar-Lezama, Armando and Synnaeve, Gabriel and Wang, Sida , booktitle =. 2024 , editor =
work page 2024
-
[16]
Mohamed Nejjar and Luca Zacharias and Fabian Stiehle and Ingo Weber , title =. J. Softw. Evol. Process. , volume =. 2025 , url =. doi:10.1002/SMR.2723 , timestamp =
-
[17]
Peixiang Zhong and Di Wang and Chunyan Miao , title =. The Thirty-Third. 2019 , url =. doi:10.1609/AAAI.V33I01.33017492 , timestamp =
- [18]
-
[19]
Llama.cpp --- Wikipedia , The Free Encyclopedia
Wikipedia contributors. Llama.cpp --- Wikipedia , The Free Encyclopedia. 2024
work page 2024
- [20]
- [21]
-
[22]
QLoRA: Efficient Finetuning of Quantized LLMs , author=. 2023 , eprint=
work page 2023
-
[23]
k-quants by ikawrakow , howpublished =
Georgi Gerganov and. k-quants by ikawrakow , howpublished =. 2023 , note =
work page 2023
- [24]
-
[25]
Xinpeng Wang and Bolei Ma and Chengzhi Hu and Leon Weber. "My Answer is C": First-Token Probabilities Do Not Match Text Answers in Instruction-Tuned Language Models , booktitle =. 2024 , url =. doi:10.18653/V1/2024.FINDINGS-ACL.441 , timestamp =
-
[26]
5th International Conference on Learning Representations,
Stephen Merity and Caiming Xiong and James Bradbury and Richard Socher , title =. 5th International Conference on Learning Representations,. 2017 , url =
work page 2017
- [27]
-
[28]
The Tenth International Conference on Learning Representations,
Tim Dettmers and Mike Lewis and Sam Shleifer and Luke Zettlemoyer , title =. The Tenth International Conference on Learning Representations,. 2022 , url =
work page 2022
-
[29]
A Comprehensive Evaluation of Quantization Strategies for Large Language Models , booktitle =
Renren Jin and Jiangcun Du and Wuwei Huang and Wei Liu and Jian Luan and Bin Wang and Deyi Xiong , editor =. A Comprehensive Evaluation of Quantization Strategies for Large Language Models , booktitle =. 2024 , url =. doi:10.18653/V1/2024.FINDINGS-ACL.726 , timestamp =
- [30]
- [31]
-
[32]
File:IEEE 754r Half Floating Point Format.svg --- Wikimedia Commons , the free media repository
Wikimedia Commons. File:IEEE 754r Half Floating Point Format.svg --- Wikimedia Commons , the free media repository. 2020
work page 2020
-
[33]
File:Bfloat16 format.svg --- Wikimedia Commons , the free media repository
Wikimedia Commons. File:Bfloat16 format.svg --- Wikimedia Commons , the free media repository. 2023
work page 2023
-
[34]
Introducing Meta Llama 3: The most capable openly available LLM to date , author=. 2024 , month=
work page 2024
-
[35]
Gemma: Introducing new state-of-the-art open models , url=
Banks, Jeanine and Warkentin, Tris , year=. Gemma: Introducing new state-of-the-art open models , url=. Google , publisher=
-
[36]
Gemma 2 is now available to researchers and developers , url=
Farabet, Clement and Warkentin, Tris , year=. Gemma 2 is now available to researchers and developers , url=. Google , publisher=
-
[37]
Microsoft Azure Blog , author=
Introducing Phi-3: Redefining what’s possible with SLMs , url =. Microsoft Azure Blog , author=. 2024 , month=
work page 2024
-
[38]
Albert Q. Jiang and Alexandre Sablayrolles and Arthur Mensch and Chris Bamford and Devendra Singh Chaplot and Diego de Las Casas and Florian Bressand and Gianna Lengyel and Guillaume Lample and Lucile Saulnier and L. Mistral 7B , journal =. 2023 , url =. doi:10.48550/ARXIV.2310.06825 , eprinttype =. 2310.06825 , timestamp =
work page internal anchor Pith review Pith/arXiv arXiv doi:10.48550/arxiv.2310.06825 2023
-
[39]
Mistral AI Large Language Models , author=
Tokenization , howpublished =. Mistral AI Large Language Models , author=
- [40]
-
[41]
Proceedings of the AAAI Conference on Artificial Intelligence , author=
What Makes Quantization for Large Language Model Hard? An Empirical Study from the Lens of Perturbation , volume=. Proceedings of the AAAI Conference on Artificial Intelligence , author=. 2024 , month=. doi:10.1609/aaai.v38i16.29765 , abstractNote=
-
[42]
Gomez and Lukasz Kaiser and Illia Polosukhin , editor =
Ashish Vaswani and Noam Shazeer and Niki Parmar and Jakob Uszkoreit and Llion Jones and Aidan N. Gomez and Lukasz Kaiser and Illia Polosukhin , editor =. Attention is All you Need , booktitle =. 2017 , url =
work page 2017
-
[43]
Peter J. Liu and Mohammad Saleh and Etienne Pot and Ben Goodrich and Ryan Sepassi and Lukasz Kaiser and Noam Shazeer , title =. 6th International Conference on Learning Representations,. 2018 , url =
work page 2018
-
[44]
Luis Perez and Lizi Ottens and Sudharshan Viswanathan , title =. CoRR , volume =. 2021 , url =. 2102.10535 , timestamp =
-
[45]
The Mathematical Theory of Communication , author=. 1949 , publisher=
work page 1949
-
[46]
Abhimanyu Dubey and Abhinav Jauhri and Abhinav Pandey and Abhishek Kadian and Ahmad Al. The Llama 3 Herd of Models , journal =. 2024 , url =. doi:10.48550/ARXIV.2407.21783 , eprinttype =. 2407.21783 , timestamp =
work page internal anchor Pith review Pith/arXiv arXiv doi:10.48550/arxiv.2407.21783 2024
-
[47]
Morgane Rivière and Shreya Pathak and Pier Giuseppe Sessa and Cassidy Hardin and Surya Bhupatiraju and Léonard Hussenot and Thomas Mesnard and Bobak Shahriari and Alexandre Ramé and Johan Ferret and Peter Liu and Pouya Tafti and Abe Friesen and Michelle Casbon and Sabela Ramos and Ravin Kumar and Charline Le Lan and Sammy Jerome and Anton Tsitsulin and Ni...
work page 2024
-
[48]
Microsoft Developer Blogs , author=
Infinite Chat using a sliding window , url=. Microsoft Developer Blogs , author=. 2023 , month=
work page 2023
-
[49]
Deep Sparse Rectifier Neural Networks , author =. Proceedings of the Fourteenth International Conference on Artificial Intelligence and Statistics , pages =. 2011 , editor =
work page 2011
-
[50]
Improving Text Embeddings with Large Language Models
Liang Wang and Nan Yang and Xiaolong Huang and Linjun Yang and Rangan Majumder and Furu Wei , editor =. Improving Text Embeddings with Large Language Models , booktitle =. 2024 , url =. doi:10.18653/V1/2024.ACL-LONG.642 , timestamp =
-
[51]
Jianlin Su and Murtadha H. M. Ahmed and Yu Lu and Shengfeng Pan and Wen Bo and Yunfeng Liu , title =. Neurocomputing , volume =. 2024 , url =. doi:10.1016/J.NEUCOM.2023.127063 , timestamp =
-
[52]
Ercegovac, Milos D. and Lang, Tomás , year=. Digital Arithmetic , publisher=
-
[53]
Amir Gholami and Sehoon Kim and Zhen Dong and Zhewei Yao and Michael W. Mahoney and Kurt Keutzer , title =. CoRR , volume =. 2021 , url =. 2103.13630 , timestamp =
-
[54]
Understanding and Overcoming the Challenges of Efficient Transformer Quantization , booktitle =
Yelysei Bondarenko and Markus Nagel and Tijmen Blankevoort , editor =. Understanding and Overcoming the Challenges of Efficient Transformer Quantization , booktitle =. 2021 , url =. doi:10.18653/V1/2021.EMNLP-MAIN.627 , timestamp =
-
[55]
The Bell system technical journal , volume=
A mathematical theory of communication , author=. The Bell system technical journal , volume=. 1948 , publisher=
work page 1948
-
[56]
Exploring Post-training Quantization in
Zhewei Yao and Xiaoxia Wu and Cheng Li and Stephen Youn and Yuxiong He , editor =. Exploring Post-training Quantization in. Thirty-Eighth. 2024 , url =. doi:10.1609/AAAI.V38I17.29908 , timestamp =
-
[57]
Sher Badshah and Hassan Sajjad , title =. CoRR , volume =. 2024 , url =. doi:10.48550/ARXIV.2405.03146 , eprinttype =. 2405.03146 , timestamp =
-
[58]
Yijun Liu and Yuan Meng and Fang Wu and Shenhao Peng and Hang Yao and Chaoyu Guan and Chen Tang and Xinzhu Ma and Zhi Wang and Wenwu Zhu , title =. CoRR , volume =. 2024 , url =. doi:10.48550/ARXIV.2406.12928 , eprinttype =. 2406.12928 , timestamp =
-
[59]
Visual Intelligence , volume =
Wei Huang and Xingyu Zheng and Xudong Ma and Haotong Qin and Chengtao Lv and Hong Chen and Jie Luo and Xiaojuan Qi and Xianglong Liu and Michele Magno , title =. Visual Intelligence , volume =. 2024 , url =. doi:10.1007/S44267-024-00070-X , timestamp =
-
[60]
Aggregating empirical evidence from data strategy studies: a case on model quantization , journal =
Santiago del Rey and Paulo S. Aggregating empirical evidence from data strategy studies: a case on model quantization , journal =. 2025 , url =. doi:10.48550/ARXIV.2505.00816 , eprinttype =. 2505.00816 , timestamp =
-
[61]
Jemin Lee and Sihyeong Park and Jinse Kwon and Jihun Oh and Yongin Kwon , title =. CoRR , volume =. 2024 , url =. doi:10.48550/ARXIV.2409.11055 , eprinttype =. 2409.11055 , timestamp =
-
[62]
Kazuki Egashira and Mark Vero and Robin Staab and Jingxuan He and Martin T. Vechev , editor =. Exploiting. Advances in Neural Information Processing Systems 38: Annual Conference on Neural Information Processing Systems 2024, NeurIPS 2024, Vancouver, BC, Canada, December 10 - 15, 2024 , year =
work page 2024
-
[63]
Beyond Perplexity: Multi-dimensional Safety Evaluation of LLM Compression
Xu, Zhichao and Gupta, Ashim and Li, Tao and Bentham, Oliver and Srikumar, Vivek. Beyond Perplexity: Multi-dimensional Safety Evaluation of LLM Compression. Findings of the Association for Computational Linguistics: EMNLP 2024. 2024. doi:10.18653/v1/2024.findings-emnlp.901
-
[64]
How Does Quantization Affect Multilingual LLM s?
Marchisio, Kelly and Dash, Saurabh and Chen, Hongyu and Aumiller, Dennis and. How Does Quantization Affect Multilingual LLM s?. Findings of the Association for Computational Linguistics: EMNLP 2024. 2024. doi:10.18653/v1/2024.findings-emnlp.935
-
[65]
Proceedings of the 41st International Conference on Machine Learning , articleno =
Egiazarian, Vage and Panferov, Andrei and Kuznedelev, Denis and Frantar, Elias and Babenko, Artem and Alistarh, Dan , title =. Proceedings of the 41st International Conference on Machine Learning , articleno =. 2024 , publisher =
work page 2024
-
[66]
LLMC : Benchmarking Large Language Model Quantization with a Versatile Compression Toolkit
Gong, Ruihao and Yong, Yang and Gu, Shiqiao and Huang, Yushi and Lv, Chengtao and Zhang, Yunchen and Tao, Dacheng and Liu, Xianglong. LLMC : Benchmarking Large Language Model Quantization with a Versatile Compression Toolkit. Proceedings of the 2024 Conference on Empirical Methods in Natural Language Processing: Industry Track. 2024. doi:10.18653/v1/2024....
-
[67]
Wang, Yubo and Ma, Xueguang and Zhang, Ge and Ni, Yuansheng and Chandra, Abhranil and Guo, Shiguang and Ren, Weiming and Arulraj, Aaran and He, Xuan and Jiang, Ziyan and Li, Tianle and Ku, Max and Wang, Kai and Zhuang, Alex and Fan, Rongqi and Yue, Xiang and Chen, Wenhu , title =. Proceedings of the 38th International Conference on Neural Information Proc...
work page 2025
-
[68]
The Twelfth International Conference on Learning Representations,
Zayne Sprague and Xi Ye and Kaj Bostrom and Swarat Chaudhuri and Greg Durrett , title =. The Twelfth International Conference on Learning Representations,. 2024 , url =
work page 2024
- [69]
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.