ptq

Quantize pretrained models to nvfp4, fp8, or int4_awq checkpoints using ModelOpt PTQ.

2.8k|332|Updated Feb 25, 2026
One-click install
npx skills add https://github.com/NVIDIA/skills --skill ptq
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: ptq
Source: https://github.com/NVIDIA/skills/tree/main/skills/Model-Optimizer/ptq
Command: npx skills add https://github.com/NVIDIA/skills --skill ptq

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Post-training quantization (PTQ) enables converting pretrained models into compact, deployment-friendly checkpoints with reduced memory footprint and faster inference using ModelOpt.

Core Features & Use Cases

  • Supports nvfp4, fp8, and int4_awq formats for HF, MoE, and VLM backbones.
  • Automates calibration, validation, and export of quantized checkpoints.
  • Use Case: quantize a Qwen3-0.6B to nvfp4 for deployment on GPU-constrained environments.

Quick Start

Quantize a pretrained model to produce a deployment-ready quantized checkpoint using ModelOpt PTQ.

Frequently Asked Questions about ptq

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I quantize a pretrained model to fp8 or nvfp4 using ModelOpt?

To quantize a pretrained model with ModelOpt, you run the PTQ workflow which automates calibration and validation to export a deployment-ready checkpoint in formats like fp8 or nvfp4.

What is post-training quantization and when do I need it for my model?

Post-training quantization (PTQ) converts pretrained models into compact, deployment-friendly checkpoints, reducing memory footprint and accelerating inference without requiring retraining.

Does ModelOpt PTQ support quantizing MoE and VLM architectures?

Yes, ModelOpt PTQ supports quantizing HuggingFace, TensorRT-LLM backbones, and both MoE and VLM architectures to formats such as nvfp4, fp8, and int4_awq.

What are the steps to export an int4_awq quantized checkpoint for a HuggingFace model?

You must prepare the environment, verify model support, execute optional remote or launcher runs for calibration, and validate the checkpoint against the model to ensure the correct quantization pattern.

Why does post-training quantization require a validation step against the checkpoint?

Post-training quantization requires validation to ensure the exported checkpoint applies the correct quantization pattern and maintains deployment-ready accuracy after calibration.