Scaling up Test-Time Compute with Latent Reasoning: A Recurrent Depth Approach

Published: 18 Sept 2025, Last Modified: 29 Oct 2025NeurIPS 2025 spotlightEveryoneRevisionsBibTeXCC BY 4.0
Keywords: test-time scaling, large language models, recurrence, reasoning, depth, universal transformers
TL;DR: We show that recurrent-depth transformers can be scaled to be effective language models, with particularly strong gains through additional compute for reasoning tasks.
Abstract: We study a novel language model architecture that is capable of scaling test-time computation by implicitly reasoning in latent space. Our model works by iterating a recurrent block, thereby unrolling to arbitrary depth at test-time. This stands in contrast to mainstream reasoning models that scale up compute by producing more tokens. Unlike approaches based on chain-of-thought, our approach does not require any specialized training data, can work with small context windows, and can capture types of reasoning that are not easily represented in words. We train a proof-of-concept model from scratch with 3.5 billion parameters and 800 billion tokens. We show that this model can effortlessly use varying levels of compute, significantly improving with additional compute especially on reasoning tasks, such as math and coding. Further, this architecture naturally reduces compute costs via zero-shot per-token adaptive compute, KV-cache sharing and speculative decoding.
Supplementary Material: zip
Primary Area: Deep learning (e.g., architectures, generative models, optimization for deep networks, foundation models, LLMs)
Submission Number: 22809
Loading