LLM quantization
GPTQ
GPTQ: Accurate Post-Training Quantization for Generative Pre-trained Transformers
Heavily superseded — a standard baseline that newer methods routinely beat
13 papers critique it · 28 beat it on benchmarks
What papers say
Verbatim critique sentences, each from a paper that cites GPTQ as a baseline.
While GPTQ significantly reduces the local layer-wise MSE, its effect of reducing the global NLL loss is minimal given the same training data and same trainable weights.
“as these techniques do not involve gradient-based optimization, unless task-specific calibration data is utilized, they can suffer substantial accuracy degradation on more challenging benchmarks, particularly text generation”
“existing PTQ approaches for LLMs minimize the layer-wise reconstruction loss while treating all tokens uniformly lin2023awq,frantar2022gptq,li2025gptqv2, without accounting for token-level informativeness or importance. Such a token-agnostic design inevitably biases the quantized model toward dominant but redundant visual features”
“However, under low-bit quantization, quantization errors from preceding layers accumulate across the network, making local-only basic reconstruction insufficient.”
“However, GPTQ and SmoothQuant~(SQ), which are strong PTQ methods for pure LLMs, do not reliably improve performance in this multimodal setting.”
“We further observe that generic PTQ methods such as GPTQ and AWQ suffer significant performance degradation under W4A16, highlighting the challenge of directly applying standard quantization techniques to VGGT.”
“the same routines collapse on sub-7B models where redundancy is scarce”
“GPTVQ accumulates quantization errors within vector quantization, leading to an inevitable increase in quantization errors as the vector length increases.”
“Despite its empirical success, the GPTQ algorithm was only presented as a sequence of greedily applied algebraic operations: the procedure picks one weight at a time, quantizes it via rounding or clipping, and then optimally updates the not-yet-quantized weights to correct for the remaining per-layer loss; it then continues with the next weight, and so on. This procedure leaves an obvious open question: why does a local greedy rule work so well globally? Current literature does not answer this question, leaving little guidance for principled extensions or failure case analysis.”
“GPTQ~frantar2022gptq poorly handles outliers due to calibration dependence”
“However, the weight updates are computed in a closed form based on second-order gradient information; this is done for each layer separately, which does not consider the dependencies among layers.”
“because GPTQ optimizes only for reconstruction accuracy, it can unintentionally increase group-targeting biases, which we aim to reduce with Fair-GPTQ”
Beaten on benchmarks
Head-to-head results where a newer method reports beating GPTQ. Values are copied from the source paper's tables — verify against the cited paper.
FrameQuant beats GPTQ
48.10 vs 0.40
Top-1 accuracy · [2-bit quantization, ViT-S]
FrameQuant: Flexible Low-Bit Quantization for TransformersReasoning-QAT beats GPTQ
15.27 vs 0.31
Avg. · [Qwen3-0.6B W2G128]
What Makes Low-Bit Quantization-Aware Training Work for Reasoning LLMs? A Systematic StudyLieQ beats GPTQ
75.55 vs 25.55
HeRo-Q beats GPTQ
70.15 vs 26.30
GSM8K · [Llama-3-8B (W3A16)]
HeRo-Q: A General Framework for Stable Low Bit Quantization via Hessian ConditioningPTQ1.61 beats GPTQ
51.77 vs 24.35
VPTQ beats GPTQ
39.9 vs 19.59
tok/s (throughput, tokens per second) · [7B, 2-bit]
VPTQ: Extreme Low-bit Vector Post-Training Quantization for Large Language ModelsBiLLM beats GPTQ
8.41 vs 74395.42
perplexity · [LLaMA2-70B 1-bit]
BiLLM: Pushing the Limit of Post-Training Quantization for LLMsSEPTQ beats GPTQ
16.20 vs 8575.29
HPTQ beats GPTQ
22.58 vs 357.69
Perplexity · [2.125 bitwidth]
The Geometry of LLM Quantization: GPTQ as Babai's Nearest Plane AlgorithmDASH-Q beats GPTQ
56.52 vs 35.66
Average zero-shot reasoning accuracy · [Llama-3.1-8B, 2-bit / 32]
Robust Ultra Low-Bit Post-Training Quantization via Stable Diagonal Curvature EstimateButterflyQuant beats GPTQ
15.40 vs 36.77
WikiText-2 Perplexity · [LLaMA2-7B]
ButterflyQuant: Ultra-low-bit LLM Quantization through Learnable Orthogonal Butterfly TransformsQuant-dLLM beats GPTQ
47.99 vs 30.60
Average · [2-bit weight quantization on Dream-7B-Instruct]
Quant-dLLM: Post-Training Extreme Low-Bit Quantization for Diffusion Large Language Models
What to use instead
Recent methods in the same sub-problem, not yet superseded in the knowledge base — arXiv benchmark leaders, not vetted production recommendations.
- May 29, 2026
- LFQLFQ: Logit-aware Final-block Quantization for Boosting the Generation Quality of Low-Bit Quantized LLMsMay 28, 2026
- ADMM-QADMM-Q: An Improved Hessian-based Weight Quantizer for Post-Training Quantization of Large Language ModelsMay 11, 2026
- May 6, 2026
- Apr 11, 2026
- Jan 21, 2026
- Grouped Lattice Vector Quantization (GLVQ)Learning Grouped Lattice Vector Quantizers for Low-Bit LLM CompressionOct 23, 2025
- Sep 28, 2025
- Bi-VLMBi-VLM: Pushing Ultra-Low Precision Post-Training Quantization Boundaries in Vision-Language ModelsSep 23, 2025
- Sep 18, 2025