Empirical Validation of Multi-Token Prediction for LLMs

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4 Jun 2025

Abstract and 1. Introduction

2. Method

3. Experiments on real data

3.1. Benefits scale with model size and 3.2. Faster inference

3.3. Learning global patterns with multi-byte prediction and 3.4. Searching for the optimal n

3.5. Training for multiple epochs and 3.6. Finetuning multi-token predictors

3.7. Multi-token prediction on natural language

4. Ablations on synthetic data and 4.1. Induction capability

4.2. Algorithmic reasoning

5. Why does it work? Some speculation and 5.1. Lookahead reinforces choice points

5.2. Information-theoretic argument

6. Related work

7. Conclusion, Impact statement, Environmental impact, Acknowledgements, and References

A. Additional results on self-speculative decoding

B. Alternative architectures

C. Training speeds

D. Finetuning

E. Additional results on model scaling behavior

F. Details on CodeContests finetuning

G. Additional results on natural language benchmarks

H. Additional results on abstractive text summarization

I. Additional results on mathematical reasoning in natural language

J. Additional results on induction learning

K. Additional results on algorithmic reasoning

L. Additional intuitions on multi-token prediction

M. Training hyperparameters

3. Experiments on real data

We demonstrate the efficacy of multi-token prediction losses by seven large-scale experiments. Section 3.1 shows how multi-token prediction is increasingly useful when growing the model size. Section 3.2 shows how the additional prediction heads can speed up inference by a factor of 3× using speculative decoding. Section 3.3 demonstrates how multi-token prediction promotes learning longer-term patterns, a fact most apparent in the extreme case of byte-level tokenization. Section 3.4 shows that 4-token predictor leads to strong gains with a tokenizer of size 32k. Section 3.5 illustrates that the benefits of multi-token prediction remain for training runs with multiple epochs. Section 3.6 showcases the rich representations promoted by pretraining with multi-token prediction losses by finetuning on the CodeContests dataset (Li et al., 2022). Section 3.7 shows that the benefits of multi-token prediction carry to natural language models, improving generative evaluations such as summarization, while not regressing significantly on standard benchmarks based on multiple choice questions and negative log-likelihoods.

To allow fair comparisons between next-token predictors and n-token predictors, the experiments that follow always compare models with an equal amount of parameters. That is, when we add n − 1 layers in future prediction heads, we remove n − 1 layers from the shared model trunk. Please refer to Table S14 for the model architectures and to Table S13 for an overview of the hyperparameters we use in our experiments.

This paper is available on arxiv under CC BY 4.0 DEED license.

Authors:

(1) Fabian Gloeckle, FAIR at Meta, CERMICS Ecole des Ponts ParisTech, and contributed equally;

(2) Badr Youbi IdrissiFAIR at Meta, LISN Université Paris-Saclay, and contributed equally;

(3) Baptiste Rozière, FAIR at Meta;

(4) David Lopez-Paz, FAIR at Meta and his the last author;

(5) Gabriel Synnaeve, FAIR at Meta and the last author.