--- title: 's1: Simple test-time scaling' license: CC-BY-4.0 license_url: https://creativecommons.org/licenses/by/4.0/ license_note: 'This note is CC BY 4.0. It links to the paper and does not reproduce it. Paper license: arXiv non-exclusive distribution (verified on arXiv abs page 2026-11-11; http://arxiv.org/licenses/nonexclusive-distrib/1.0/).' source: https://iinventedlight.com/library/notes/2501-19393-s1.md source_license: 'arXiv default (non-exclusive distribution license)' attribution: 'Pointer note by iinventedlight (AI-assisted). Links to: Niklas Muennighoff, Zitong Yang, Weijia Shi, Xiang Lisa Li, Li Fei-Fei, et al. (10 authors), s1: Simple test-time scaling (arXiv). This note does not reproduce the paper.' author: 'iinventedlight (AI-assisted)' date: 2026-11-11 status: published approved_by: "Cole Withington, 2026-11-11 20:58 PT, Grok Bot chat widget t1717s7407: \"Publish all 100 including the LLMs Encode Clinical Knowledge note\"" checked_on: 2026-11-11 as_of: 2026-11-11 confidence: medium untested: 'Pointer note only. Abs page read 2026-11-11. The paper is not reproduced here.' category: arxiv topic_area: 'ai-research: reasoning' tags: arxiv, pointer, reasoning arxiv_id: 2501.19393 alias: 2501.19393-s1 format: pointer type: pointer sources: - id: S1 title: 's1: Simple test-time scaling' publisher: arXiv authors: 'Niklas Muennighoff, Zitong Yang, Weijia Shi, Xiang Lisa Li, Li Fei-Fei, et al. (10 authors)' url: https://arxiv.org/abs/2501.19393 version_read: 'v3 (1 Mar 2025)' accessed: 2026-11-11 license: 'arXiv default (non-exclusive distribution license)' --- # s1: Simple test-time scaling ## Summary s1: Simple test-time scaling (2025), by Niklas Muennighoff, Zitong Yang, Weijia Shi, Xiang Lisa Li, Li Fei-Fei, and coauthors, is at https://arxiv.org/abs/2501.19393. The authors curate s1K, a set of 1,000 questions paired with reasoning traces, chosen using three criteria they test in ablations: difficulty, diversity, and quality. They develop budget forcing to control test-time compute by forcefully terminating the model's thinking process or lengthening it by appending Wait when the model tries to end. After supervised finetuning of Qwen2.5-32B-Instruct on s1K and using budget forcing, they report that s1-32B exceeds o1-preview on competition math questions by up to 27% (MATH and AIME24), and that scaling with budget forcing can move AIME24 from 50% to 57%. They say the model, data, and code are open-source at https://github.com/simplescaling/s1. Title, authors, abstract, and comments were taken from the arXiv abs page. The version is v3 (1 Mar 2025), submitted 31 Jan 2025. ## Claims Pointer notes do not quote the paper. See Verification and Sources for the link and license. ## Verification - Format: pointer note only. The paper is not reproduced here. - Why it matters: It matters because it offers a small, openly described recipe for test-time scaling at a moment when many people were trying to reproduce the behavior of closed reasoning models. - Reproduced: not reproduced (2026-11-11). - Related work: Related notes already in the library include [Self-Consistency](https://iinventedlight.com/library/notes/2203-11171-self-consistency/) and [Self-Adapting Language Models](https://iinventedlight.com/library/notes/2506-10943-seal-self-adapting-language-models/). - Limits: This is a pointer note only. AIME and MATH comparisons are the authors' reported results from the v3 paper (1 Mar 2025). - License: arXiv default (non-exclusive distribution license) on the abs page (2026-11-11; http://arxiv.org/licenses/nonexclusive-distrib/1.0/). Submitted 31 Jan 2025 (v1); last revised 1 Mar 2025 (v3). Sources: [S1] https://arxiv.org/abs/2501.19393, v3 (1 Mar 2025). checked_on: 2026-11-11. Paper license: arXiv non-exclusive distribution; this note links to it and does not reproduce it. The note itself is CC BY 4.0. ## When to apply Use when looking for a simple, openly described test-time scaling recipe and the s1K data release. ## Facts - id: F1 claim: 'The s1 paper curates s1K, a dataset of 1,000 questions paired with reasoning traces, selected for difficulty, diversity, and quality.' confidence: medium date: 2026-11-11 sources: [S1] license: CC-BY-4.0 - id: F2 claim: 'The authors describe budget forcing, which can stop or extend a model''s thinking process, including by appending Wait when the model tries to end.' confidence: medium date: 2026-11-11 sources: [S1] license: CC-BY-4.0 - id: F3 claim: 'After supervised finetuning of Qwen2.5-32B-Instruct on s1K with budget forcing, they report that s1-32B exceeds o1-preview on competition math questions by up to 27% on MATH and AIME24, and that budget forcing can move AIME24 from 50% to 57%.' confidence: medium date: 2026-11-11 sources: [S1] license: CC-BY-4.0 ## Sources - [S1] arXiv 2501.19393, https://arxiv.org/abs/2501.19393. Paper license: arXiv default (non-exclusive distribution license). v3 (1 Mar 2025). Accessed 2026-11-11. This note links to the paper and does not reproduce it. License: this note is CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Pointer by iinventedlight (AI-assisted). Paper license: arXiv non-exclusive distribution; this note links to it and does not reproduce it. --- Agents: [/agents.md](/agents.md) | [/.well-known/agent-library.json](/.well-known/agent-library.json).