MF-QAT: Multi-Format Quantization-Aware Training for Elastic Inference

Zifei Xu, Sayeh Sharify, Hesham Mostafa


Abstract
Quantization-aware training (QAT) is typically performed for a single target numeric format, while practical deployments often need to choose numerical precision at inference time based on hardware support or runtime constraints. We study multi-format QAT, which fine-tunes a pretrained model for multiple precisions within a microscaling format family. Across the evaluated language models, it achieves accuracy close to single-format QAT at most target precisions and generalizes to intermediate precisions unseen during fine-tuning, although the lowest-precision MXINT setting remains challenging. To make these models deployable from a single quantized checkpoint, we propose Slice-and-Scale, which converts a higher-precision MXINT or MXFP anchor to lower precisions by transforming both element values and shared block scales, without access to the original full-precision weights. Fine-tuning through this conversion produces an anchor checkpoint whose converted variants closely track standard multi-format QAT in language-modeling evaluations. Together, multi-format QAT and Slice-and-Scale enable precision selection from one stored checkpoint within each format family.
Anthology ID:
2026.findings-aacl.110
Volume:
Findings of the Association for Computational Linguistics: IJCNLP-AACL 2026
Month:
November
Year:
2026
Address:
Hengqin, China
Editors:
Yue Zhang, Ruifeng Xu, Ayu Purwarianti, Tong Rong, Jun Suzuki
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
2168–2188
Language:
URL:
https://aclanthology.org/2026.findings-aacl.110/
DOI:
Bibkey:
Cite (ACL):
Zifei Xu, Sayeh Sharify, and Hesham Mostafa. 2026. MF-QAT: Multi-Format Quantization-Aware Training for Elastic Inference. In Findings of the Association for Computational Linguistics: IJCNLP-AACL 2026, pages 2168–2188, Hengqin, China. Association for Computational Linguistics.
Cite (Informal):
MF-QAT: Multi-Format Quantization-Aware Training for Elastic Inference (Xu et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-aacl.110.pdf