LFM2.5-2.6B-Base / README.md
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metadata
library_name: transformers
license: other
license_name: lfm1.0
license_link: LICENSE
language:
  - ar
  - zh
  - en
  - fr
  - de
  - hi
  - id
  - it
  - ja
  - ko
  - pl
  - pt
  - ru
  - es
  - th
  - vi
pipeline_tag: text-generation
tags:
  - liquid
  - lfm2.5
  - edge
base_mode: LiquidAI/LFM2.5-2.6B-Base
Liquid AI
Try LFM β€’ Docs β€’ LEAP β€’ Discord

LFM2.5-2.6B

LFM2.5 is a new family of hybrid models designed for on-device deployment. It builds on the LFM2 architecture with extended pre-training and reinforcement learning.

Find more information about LFM2.5 in our blog post.

πŸ—’οΈ Model Details

Model Parameters Description
LFM2.5-2.6B-Base 2.6B Pre-trained base model for fine-tuning
LFM2.5-2.6B 2.6B Post-trained for agentic workloads

LFM2.5-2.6B-Base is the pre-trained text-only checkpoint, used to create all the LFM2.5-2.6B variants. It has the following features:

  • Total parameters: 2.69B
  • Number of layers: 30 (22 double-gated short convolution blocks + 8 GQA)
  • Training budget: 34 trillion tokens
  • Vocabulary size: 128,000
  • Context length: 131,072 tokens
  • Languages: English, Arabic, Chinese, French, German, Italian, Japanese, Korean, Portuguese, Spanish, Vietnamese, Thai, Indonesian, Hindi, Russian, Polish
Model Description
LFM2.5-2.6B Original model checkpoint in native format. Best for fine-tuning or inference with Transformers, vLLM, and SGLang.
LFM2.5-2.6B-GGUF Quantized format for llama.cpp and compatible tools. Optimized for CPU inference and local deployment with reduced memory usage.
LFM2.5-2.6B-ONNX ONNX Runtime format for cross-platform deployment. Enables hardware-accelerated inference across diverse environments (cloud, edge, mobile).
LFM2.5-2.6B-MLX MLX format for Apple Silicon. Optimized for fast inference on Mac devices using the MLX framework.

This pre-trained checkpoint is only recommended for tasks that require heavy fine-tuning, like language-specific (e.g., Japanese) or domain-specific (e.g., medical) assistants, training on proprietary data, or experimenting with novel post-training approaches.

πŸƒ Inference

LFM2.5 is supported by many inference frameworks. See the Inference documentation for the full list.

Name Description Docs Notebook
Transformers Simple inference with direct access to model internals. Link Colab link
vLLM High-throughput production deployments with GPU. Link Colab link
llama.cpp Cross-platform inference with CPU offloading. Link Colab link
MLX Apple's machine learning framework optimized for Apple Silicon. Link β€”
LM Studio Desktop application for running LLMs locally. Link β€”
SGLang High-throughput production deployments with GPU. Link -

Quick start with Transformers (compatible with transformers>=5.0.0):

from transformers import AutoModelForCausalLM, AutoTokenizer, TextStreamer

model_id = "LiquidAI/LFM2.5-2.6B-Base"
model = AutoModelForCausalLM.from_pretrained(
    model_id,
    device_map="auto",
    dtype="bfloat16",
#   attn_implementation="flash_attention_2" <- uncomment on compatible GPU
)
tokenizer = AutoTokenizer.from_pretrained(model_id)
streamer = TextStreamer(tokenizer, skip_prompt=True, skip_special_tokens=True)

prompt = "What is C. elegans?"

input_ids = tokenizer.apply_chat_template(
    [{"role": "user", "content": prompt}],
    add_generation_prompt=True,
    return_tensors="pt",
    tokenize=True,
)["input_ids"].to(model.device)

output = model.generate(
    input_ids,
    do_sample=True,
    temperature=0.2,
    top_k=80,
    repetition_penalty=1.05,
    max_new_tokens=512,
    streamer=streamer,
)

πŸ”§ Fine-Tuning

We recommend fine-tuning LFM2.5 for your specific use case to achieve the best results.

Name Description Docs Notebook
CPT (Unsloth) Continued Pre-Training using Unsloth for text completion. Link Colab link
CPT (Unsloth) Continued Pre-Training using Unsloth for translation. Link Colab link
SFT (Unsloth) Supervised Fine-Tuning with LoRA using Unsloth. Link Colab link
SFT (TRL) Supervised Fine-Tuning with LoRA using TRL. Link Colab link
DPO (TRL) Direct Preference Optimization with LoRA using TRL. Link Colab link
GRPO (Unsloth) GRPO with LoRA using Unsloth. Link Colab link
GRPO (TRL) GRPO with LoRA using TRL. Link Colab link

πŸ“¬ Contact

Citation

@article{liquidAI202626B,
  author  = {Liquid AI},
  title   = {LFM2.5-2.6B: Agents Everywhere},
  journal = {Liquid AI Blog},
  year    = {2026},
  note    = {www.liquid.ai/blog/lfm2-5-2-6b},
}
@article{liquidai2025lfm2,
  title   = {LFM2 Technical Report},
  author  = {Liquid AI},
  journal = {arXiv preprint arXiv:2511.23404},
  year    = {2025}
}