Light-R1: Curriculum SFT, DPO and RL for Long COT from Scratch and Beyond
On the map: LLM reasoning → Reasoning benchmarks and evaluation
Abstract (arXiv)
This paper introduces Light-R1, an open-source suite for training long reasoning models using reproducible and cost-effective methodology. Given the proprietary nature of data used in the DeepSeek-R1 series, we develop an alternative approach leveraging exclusively public data and models. Our curriculum training progressively increases data difficulty, combined with multi-staged post-training. Our Light-R1-32B model, trained from Qwen2.5-32B-Instruct, outperforms DeepSeek-R1-Distill-Qwen-32B in math reasoning. Experimental results show that this curriculum approach becomes more effective when distinct, diverse datasets are available for different training stages: fine-tuning DeepSeek-R1-Distilled models (pre-tuned by DeepSeek team on proprietary data) with 3,000 challenging examples from our curriculum dataset yielded state-of-the-art 7B and 14B models, while the 32B model, Light-R1-32B-DS performed comparably to QwQ-32B and DeepSeek-R1. Furthermore, we extend our work by applying GRPO on long reasoning models. Our final Light-R1-14B-DS achieves SOTA performance among 14B models in math, with AIME24 & 25 scores of 74.0 and 60.2 respectively, surpassing many 32B models and DeepSeek-R1-Distill-Llama-70B. Despite math-focused training, Light-R1-14B-DS demonstrates strong cross-domain generalization. Light-R1 represents a significant advancement in making sophisticated reasoning models more accessible and implementable in real-world applications. Our models, training data and code have been made available at https://github.com/Qihoo360/Light-R1.
Key facts. Cited by 175 papers in the map (data through 14 Oct 2026). Placed in Reasoning benchmarks and evaluation, one of 17 directions in LLM reasoning. Builds on 30 of its 48 references that are in the map. First posted on arXiv 13 Mar 2025.
Builds on
30 of 48 references.
References · 30
- 2017Proximal Policy Optimization Algorithmscited by 15,215
- 2024DeepSeekMath: Pushing the Limits of Mathematical Reasoning in Open Language Modelscited by 9,379
- 2023Direct Preference Optimization: Your Language Model is Secretly a Reward Modelcited by 8,065
- 2025DeepSeek-R1: Incentivizing Reasoning Capability in LLMs via Reinforcement Learningcited by 6,330
- 2021Measuring Mathematical Problem Solving With the MATH Datasetcited by 5,371
- 2023Let's Verify Step by Stepcited by 3,789
- 2023GPQA: A Graduate-Level Google-Proof Q&A Benchmarkcited by 2,879
- 2024HybridFlow: A Flexible and Efficient RLHF Frameworkcited by 2,057
- 2015High-Dimensional Continuous Control Using Generalized Advantage Estimationcited by 2,026
- 2025s1: Simple test-time scalingcited by 1,341
- 2025Kimi k1.5: Scaling Reinforcement Learning with LLMscited by 1,210
- 2023Math-Shepherd: Verify and Reinforce LLMs Step-by-step without Human Annotationscited by 928
18 more
- 2023TIES-Merging: Resolving Interference When Merging Modelscited by 818
- 2023MetaMath: Bootstrap Your Own Mathematical Questions for Large Language Modelscited by 735
- 2023WizardMath: Empowering Mathematical Reasoning for Large Language Models via Reinforced Evol-Instructcited by 625
- 2025Process Reinforcement through Implicit Rewardscited by 504
- 2025LIMO: Less is More for Reasoningcited by 498
- 2025Demystifying Long Chain-of-Thought Reasoning in LLMscited by 326
- 2024Omni-MATH: A Universal Olympiad Level Mathematic Benchmark For Large Language Modelscited by 284
- 2024OpenMathInstruct-2: Accelerating AI for Math with Massive Open-Source Instruction Datacited by 200
- 2025MiniMax-01: Scaling Foundation Models with Lightning Attentioncited by 166
- 2024Imitate, Explore, and Self-Improve: A Reproduction Report on Slow-thinking Reasoning Systemscited by 164
- 2025LIMR: Less is More for RL Scalingcited by 139
- 2024The Good, The Bad, and The Greedy: Evaluation of LLMs Should Not Ignore Non-Determinismcited by 116
- 2025Big-Math: A Large-Scale, High-Quality Math Dataset for Reinforcement Learning in Language Modelscited by 109
- 2025What's Behind PPO's Collapse in Long-CoT? Value Optimization Holds the Secretcited by 98
- 2024Noise Contrastive Alignment of Language Models with Explicit Rewardscited by 85
- 2025Agent-R: Training Language Model Agents to Reflect via Iterative Self-Trainingcited by 82
- 2024Training Large Language Models for Reasoning through Reverse Curriculum Reinforcement Learningcited by 65
- 2025RedStar: Does Scaling Long-CoT Data Unlock Better Slow-Reasoning Systems?cited by 60
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Citing papers per year: 2025: 130; 2026: 45.
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- 2025Stop Overthinking: A Survey on Efficient Reasoning for Large Language Modelscited by 464
- 2025VL-Rethinker: Incentivizing Self-Reflection of Vision-Language Models with Reinforcement Learningcited by 323
- 2025Reinforcement Learning for Reasoning in Large Language Models with One Training Examplecited by 295
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- 2025Spurious Rewards: Rethinking Training Signals in RLVRcited by 209
- 2025A Survey of Reinforcement Learning for Large Reasoning Modelscited by 180
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- 2025Learning What Reinforcement Learning Can't: Interleaved Online Fine-Tuning for Hardest Questionscited by 97
38 more
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- 2025GRPO-LEAD: A Difficulty-Aware Reinforcement Learning Approach for Concise Mathematical Reasoning in Language Modelscited by 82
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- 2025UFT: Unifying Supervised and Reinforcement Fine-Tuningcited by 59
- 2025SRPO: Enhancing Multimodal LLM Reasoning via Reflection-Aware Reinforcement Learningcited by 57
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- 2025Klear-Reasoner: Advancing Reasoning Capability via Gradient-Preserving Clipping Policy Optimizationcited by 39
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- 2025Fine-Grained Preference Optimization Improves Spatial Reasoning in VLMscited by 32
- 2025Nemotron-CrossThink: Scaling Self-Learning beyond Math Reasoningcited by 31
- 2026Purified OPSD: On-Policy Self-Distillation Without Losing How to Thinkcited by 31
- 2025100 Days After DeepSeek-R1: A Survey on Replication Studies and More Directions for Reasoning Language Modelscited by 30
- 2025SPEED-RL: Faster Training of Reasoning Models via Online Curriculum Learningcited by 29
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- 2025Stable Reinforcement Learning for Efficient Reasoningcited by 27
- 2025Table-R1: Inference-Time Scaling for Table Reasoningcited by 24
- 2025A Survey on Agentic Multimodal Large Language Modelscited by 23
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- 2025CME-CAD: Heterogeneous Collaborative Multi-Expert Reinforcement Learning for CAD Code Generationcited by 19
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50 most cited of 175 All 175 (JSON)
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- 2026Reflective Recovery: A Self-Supervised Method for Reasoning by Learning from Mistakes24 Jul 2026
- 2026Purified OPSD: On-Policy Self-Distillation Without Losing How to Think2 Jul 2026
- 2026SEAD: Competence-Aware On-Policy Distillation via Entropy-Guided Supervision26 Jun 2026
- 2026TRACE: A Unified Rollout Budget Allocation Framework for Efficient Agentic Reinforcement Learning9 Jun 2026
- 2026Attention Amnesia in Hybrid LLMs: When CoT Fine-Tuning Breaks Long-Range Recall, and How to Fix It9 Jun 2026
- 2026sGPO: Trading Inference FLOPs for Training Efficiency in RLVR7 Jun 2026
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- 2026What properties of reasoning supervision are associated with improved downstream model quality?13 May 2026
- 2026DARE: Difficulty-Adaptive Reinforcement Learning with Co-Evolved Difficulty Estimation9 May 2026
- 2026DUET: Optimize Token-Budget Allocation for Reinforcement Learning with Verifiable Rewards8 May 2026
- 2026Omni-Fake: Benchmarking Unified Multimodal Social Media Deepfake Detection2 May 2026
- 2026Decouple before Integration: Test-time Synthesis of SFT and RLVR Task Vectors1 May 2026
- 2026RS-HyRe-R1: A Hybrid Reward Mechanism to Overcome Perceptual Inertia for Remote Sensing Images Understanding19 Apr 2026
- 2026Tracing the Roots: A Multi-Agent Framework for Uncovering Data Lineage in Post-Training LLMs12 Apr 2026
- 2026SPARD: Self-Paced Curriculum for RL Alignment via Integrating Reward Dynamics and Data Utility9 Apr 2026
- 2026Offline Exploration-Aware Fine-Tuning for Long-Chain Mathematical Reasoning17 Mar 2026
- 2026Dynamics-Predictive Sampling for Active RL Finetuning of Large Reasoning Models11 Mar 2026
- 2026PlayWorld: Learning Robot World Models from Autonomous Play9 Mar 2026
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- 2026Exposing Weaknesses of Large Reasoning Models through Graph Algorithm Problems6 Feb 2026
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- 2026P2S: Probabilistic Process Supervision for General-Domain Reasoning Question Answering28 Jan 2026
- 2026Group Distributionally Robust Optimization-Driven Reinforcement Learning for LLM Reasoning27 Jan 2026
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- 2026Teaching Models to Teach Themselves: Reasoning at the Edge of Learnability26 Jan 2026
- 2026Teaching Large Reasoning Models Effective Reflection19 Jan 2026
- 2026Training-Trajectory-Aware Token Selection15 Jan 2026
- 2026MathMixup: Boosting LLM Mathematical Reasoning with Difficulty-Controllable Data Synthesis and Curriculum Learning14 Jan 2026
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- 2026ReasonTabQA: A Comprehensive Benchmark for Table Question Answering from Real World Industrial Scenarios12 Jan 2026
- 2026Group Pattern Selection Optimization: Let LRMs Pick the Right Pattern for Reasoning12 Jan 2026
- 2026Distilling the Thought, Watermarking the Answer: A Principle Semantic Guided Watermark for Large Reasoning Models8 Jan 2026
- 2026Logics-STEM: Empowering LLM Reasoning via Failure-Driven Post-Training and Document Knowledge Enhancement4 Jan 2026
- 2025CME-CAD: Heterogeneous Collaborative Multi-Expert Reinforcement Learning for CAD Code Generation29 Dec 2025
- 2025DVPO: Distributional Value Modeling-based Policy Optimization for LLM Post-Training3 Dec 2025
- 2025Asking like Socrates: Socrates helps VLMs understand remote sensing images27 Nov 2025
- 2025Think Before You Prune: Selective Self-Generated Calibration for Pruning Large Reasoning Models24 Nov 2025
- 2025Provable Benefit of Curriculum in Transformer Tree-Reasoning Post-Training10 Nov 2025
50 newest of 175 All 175 (JSON)
- 2025Stop Overthinking: A Survey on Efficient Reasoning for Large Language Modelscited by 464
- 2025VL-Rethinker: Incentivizing Self-Reflection of Vision-Language Models with Reinforcement Learningcited by 323
- 2025Reinforcement Learning for Reasoning in Large Language Models with One Training Examplecited by 295
- 2025Reinforcement Learning with Verifiable Rewards Implicitly Incentivizes Correct Reasoning in Base LLMscited by 289
- 2025Learning to Reason under Off-Policy Guidancecited by 281
- 2025A Survey on Test-Time Scaling in Large Language Models: What, How, Where, and How Well?cited by 223
- 2025Skywork-Reward-V2: Scaling Preference Data Curation via Human-AI Synergycited by 214
- 2025Spurious Rewards: Rethinking Training Signals in RLVRcited by 209
- 2025A Survey of Reinforcement Learning for Large Reasoning Modelscited by 180
- 2025Skywork Open Reasoner 1 Technical Reportcited by 165
- 2025Self-Evolving Curriculum for LLM Reasoningcited by 112
- 2025Learning What Reinforcement Learning Can't: Interleaved Online Fine-Tuning for Hardest Questionscited by 97
12 most cited of 143 All 143 (JSON)
- 2026Selecting Diverse SFT Traces Improves Post-RL Generalization27 Sep 2026
- 2026Towards Eliminating Catastrophic Forgetting in the Curriculum Learning of Math Reasoning Tasks27 Sep 2026
- 2026On-Policy Self-Distillation without Any Supervision6 Aug 2026
- 2026Reflective Recovery: A Self-Supervised Method for Reasoning by Learning from Mistakes24 Jul 2026
- 2026Purified OPSD: On-Policy Self-Distillation Without Losing How to Think2 Jul 2026
- 2026Attention Amnesia in Hybrid LLMs: When CoT Fine-Tuning Breaks Long-Range Recall, and How to Fix It9 Jun 2026
- 2026LANG: Reinforcement Learning for Multilingual Reasoning with Language-Adaptive Hint Guidance21 May 2026
- 2026Knowledge-to-Verification: Exploring RLVR for LLMs in Knowledge-Intensive Domains18 May 2026
- 2026What properties of reasoning supervision are associated with improved downstream model quality?13 May 2026
- 2026DARE: Difficulty-Adaptive Reinforcement Learning with Co-Evolved Difficulty Estimation9 May 2026
- 2026Offline Exploration-Aware Fine-Tuning for Long-Chain Mathematical Reasoning17 Mar 2026
- 2026Dynamics-Predictive Sampling for Active RL Finetuning of Large Reasoning Models11 Mar 2026
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- 2025Tool-R1: Sample-Efficient Reinforcement Learning for Agentic Tool Use16 Sep 2025
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- 2026SEAD: Competence-Aware On-Policy Distillation via Entropy-Guided Supervision26 Jun 2026
- 2026Self-Distilled Policy Gradient2 Jun 2026
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- 2026Omni-Fake: Benchmarking Unified Multimodal Social Media Deepfake Detection2 May 2026
- 2026Decouple before Integration: Test-time Synthesis of SFT and RLVR Task Vectors1 May 2026
- 2026SPARD: Self-Paced Curriculum for RL Alignment via Integrating Reward Dynamics and Data Utility9 Apr 2026
- 2026GAC: Stabilizing Asynchronous RL Training for LLMs via Gradient Alignment Control2 Mar 2026
- 2026Actor-Curator: Co-adaptive Curriculum Learning via Policy-Improvement Bandits for RL Post-Training24 Feb 2026
- 2025CME-CAD: Heterogeneous Collaborative Multi-Expert Reinforcement Learning for CAD Code Generation29 Dec 2025
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