# Elucidating the Design Space of FP4 training

arXiv: https://arxiv.org/abs/2509.17791 · HTML: https://mlsanity.com/paper/2509.17791/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- Builds on 19 of its 25 references that are in the map.
- First posted on arXiv 22 Sep 2025.

## Builds on (most cited first, 19 of 19)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [On the Opportunities and Risks of Foundation Models](https://mlsanity.com/paper/2108.07258/) (2021)
- [Mixed Precision Training](https://mlsanity.com/paper/1710.03740/) (2017)
- [Transformers in Vision: A Survey](https://mlsanity.com/paper/2101.01169/) (2021)
- [QuIP#: Even Better LLM Quantization with Hadamard Incoherence and Lattice Codebooks](https://mlsanity.com/paper/2402.04396/) (2024)
- [SVDQuant: Absorbing Outliers by Low-Rank Components for 4-Bit Diffusion Models](https://mlsanity.com/paper/2411.05007/) (2024)
- [On The Computational Complexity of Self-Attention](https://mlsanity.com/paper/2209.04881/) (2022)
- [Scaling FP8 training to trillion-token LLMs](https://mlsanity.com/paper/2409.12517/) (2024)
- [Optimizing Large Language Model Training Using FP4 Quantization](https://mlsanity.com/paper/2501.17116/) (2025)
- [FP4 All the Way: Fully Quantized Training of LLMs](https://mlsanity.com/paper/2505.19115/) (2025)
- [Quartet: Native FP4 Training Can Be Optimal for Large Language Models](https://mlsanity.com/paper/2505.14669/) (2025)
- [Recipes for Pre-training LLMs with MXFP8](https://mlsanity.com/paper/2506.08027/) (2025)
- [Oscillation-Reduced MXFP4 Training for Vision Transformers](https://mlsanity.com/paper/2502.20853/) (2025)
- [Unit Scaling: Out-of-the-Box Low-Precision Training](https://mlsanity.com/paper/2303.11257/) (2023)
- [Low-Precision Training of Large Language Models: Methods, Challenges, and Opportunities](https://mlsanity.com/paper/2505.01043/) (2025)
- [Towards Efficient Pre-training: Exploring FP4 Precision in Large Language Models](https://mlsanity.com/paper/2502.11458/) (2025)
- [GradientStabilizer:Fix the Norm, Not the Gradient](https://mlsanity.com/paper/2502.17055/) (2025)
- [On Stochastic Rounding with Few Random Bits](https://mlsanity.com/paper/2504.20634/) (2025)
- [Characterization and Mitigation of Training Instabilities in Microscaling Formats](https://mlsanity.com/paper/2506.20752/) (2025)

## Built on by (most cited first, 4 of 4)

- [Full-Stack FP4: Stable LLM Pretraining with Quantized Projections, Optimizers, and Attention](https://mlsanity.com/paper/2607.04422/) (2026)
- [HiFloat4 Format for Language Model Pre-training on Ascend NPUs](https://mlsanity.com/paper/2604.08826/) (2026)
- [UE5M3 FP4 Block Scaling for Stable Language Model Pretraining](https://mlsanity.com/paper/2609.02846/) (2026)
- [Format-Aware Fusion for Fast FP4 Pretraining](https://mlsanity.com/paper/2610.00053/) (2026)

## Abstract (arXiv)

The increasing computational demands of foundation models have spurred research into low-precision training, with 4-bit floating-point (textttFP4) formats emerging as a frontier for maximizing hardware throughput. While numerous techniques have been proposed to stabilize textttFP4 training, they often present isolated solutions with varying, and not always clear, computational overheads. This paper aims to provide a unified view of the design space of textttFP4 training. We introduce a comprehensive, quantisation gradient-based framework for microscaling quantization that allows for a theoretical analysis of the computational costs associated with different stabilization methods on both the forward and backward passes. Using a simulator built on this framework, we conduct an extensive empirical study across a wide range of machine learning tasks, including regression, image classification, diffusion models, and language models. By systematically evaluating thousands of combinations of techniques, such as novel gradient approximations, rounding strategies, and scaling methods, we identify which configurations offer the most favourable performance-to-overhead trade-off. We find that the techniques enabling the best trade-off involve carefully combining Hadamard transformations, tensor scaling and stochastic rounding. We further find that using textttUE5M3 as a scaling factor potentially offers a good compromise between range and precision with manageable computational overhead.
