What are the hardware requirements for VibeThinker 1.5B?

VibeThinker 1.5B requires approximately 3.5 GB of VRAM and supports a context window of 128K tokens. Quantized variants may run on less VRAM; see the Quantized Models section on this page.

Who developed VibeThinker 1.5B and how large is it?

VibeThinker 1.5B is developed by WeiboAI, a model with 1.5b parameters. The model is published as open weights on Hugging Face and indexed on LLM Explorer with full benchmark history.

Where can I download or evaluate VibeThinker 1.5B?

VibeThinker 1.5B is hosted on Hugging Face and linked from this page. LLM Explorer also lists quantized variants and similar alternatives if available.

VibeThinker 1.5B by WeiboAI — VRAM 3.5GB, 128K context

Name: VibeThinker 1.5B
Author: WeiboAI

VibeThinker 1.5B is an open-source language model by WeiboAI. Features: 1.5b LLM, VRAM: 3.5GB, Context: 128K, License: mit, LLM Explorer Score: 0.29.

Arxiv:2511.06221 Base model:finetune:qwen/qwen2... Base model:qwen/qwen2.5-math-1... Code Conversational Deploy:azure En Endpoints compatible Gpqa Math Qwen2 Region:us Safetensors

Model Card on HF 🤗: https://huggingface.co/WeiboAI/VibeThinker-1.5B

VibeThinker 1.5B Parameters and Internals

LLM Name	VibeThinker 1.5B
Repository 🤗	https://huggingface.co/WeiboAI/VibeThinker-1.5B
Base Model(s)	Qwen/Qwen2.5-Math-1.5B Qwen/Qwen2.5-Math-1.5B
Model Size	1.5b
Required VRAM	3.5 GB
Updated	2026-07-24
Maintainer	WeiboAI
Model Type	qwen2
Model Files	3.5 GB
Supported Languages	en
Model Architecture	Qwen2ForCausalLM
License	mit
Context Length	131072
Model Max Length	131072
Transformers Version	4.56.1
Tokenizer Class	Qwen2Tokenizer
Padding Token	<\|endoftext\|>
Vocabulary Size	151936
Errors	replace

Rank the VibeThinker 1.5B capabilities

Have you tried this model? Rate its performance — this feedback helps the ML community find the right model for their needs.

Instruction Following and Task Automation
Factuality and Completeness of Knowledge
Censorship and Alignment
Data Analysis and Insight Generation
Text Generation
Text Summarization and Feature Extraction
Code Generation
Multi-Language Support and Translation

Quantized Models of the VibeThinker 1.5B

Model	Likes	Downloads	VRAM
VibeThinker 1.5B Mlx 4bit	26	1055	0 GB

Best Alternatives to VibeThinker 1.5B

Best Alternatives	Context / RAM	Downloads	Likes
Qwen2.5 1.5B 1.3M Stretched	1280K / 3.1 GB	27	0
ReaderLM V2	500K / 3.1 GB	35356	804
Reader Lm 1.5B	250K / 3.1 GB	385	608
DeepSeek R1 Distill Qwen 1.5B	128K / 3.5 GB	600051	1545
Ko R1 1.5B Preview	128K / 7.1 GB	8	9
Qwen2.5 1.5B	128K / 3.1 GB	863295	203
...FT Tulu3 Decontaminated Masked	128K / 3.1 GB	167	0
Seq Monkey Pretrain Base 1.5B	128K / 3.5 GB	37	0
Qwen2 1.5B	128K / 3.1 GB	195380	102
Polyalign Qwen2.5 1.5B En Sft	128K / 6.2 GB	40	0

Note: green Score (e.g. "73.2") means that the model is better than WeiboAI/VibeThinker-1.5B.