EXL2 vs GPTQ: which quantization format should you use?

Compared on hardware support, runtime, quality and what the 79-model index actually ships.

At a glance

EXL2 vs GPTQ: which quantization format should you use?
EXL2GPTQ
Runs onNVIDIA GPU (Ampere+ recommended)NVIDIA GPU (CUDA)
RuntimeExLlamaV2 · TabbyAPIauto-gptq · vLLM · TGI
Best forMax single-GPU performanceLegacy server deployment
Adoption estimate32%28%
Models in this index21 / 794 / 79

EXL2

ExLlamaV2 format. Mixed-precision per-layer quantization — best accuracy-per-bit ratio. Fastest single-GPU inference available.

Strengths

  • Fastest GPU inference
  • Best accuracy per bit
  • Ultra-low 2bpw option

Trade-offs

  • NVIDIA only
  • Steeper learning curve

GPTQ

GPT Quantization — one of the first mainstream post-training methods. Wide framework compatibility; being gradually superseded by AWQ.

Strengths

  • Wide compatibility
  • Mature ecosystem
  • Works with HF transformers

Trade-offs

  • Slow quantization process
  • Lower accuracy than AWQ

Models that ship both

No model in this index ships both formats, so there is no like-for-like row to show. The comparison above is editorial.

Which to choose