Molmo is a family of open vision-language models developed by the Allen Institute for AI. Molmo models are trained on PixMo, a dataset of 1 million, highly-curated image-text pairs. It has state-of-the-art performance among multimodal models with a similar size while being fully open-source. You can find all models in the Molmo family here. Learn more about the Molmo family in our announcement blog post or the paper.

Molmo 72B is based on Qwen2-72B and uses OpenAI CLIP as vision backbone. Molmo-72B achieves the highest academic benchmark score and ranks second on human evaluation, just slightly behind GPT-4o.

This checkpoint is a preview of the Molmo release. All artifacts used in creating Molmo (PixMo dataset, training code, evaluations, intermediate checkpoints) will be made available at a later date, furthering our commitment to open-source AI development and reproducibility.

Sign up here to be the first to know when artifacts are released.

Quick links:

💬 Demo
📂 All Models
📃 Paper
🎥 Blog with Videos

Quick Start

To run Molmo, first install dependencies:

pip install einops torchvision

Then, follow these steps:

python

from transformers import AutoModelForCausalLM, AutoProcessor, GenerationConfig
from PIL import Image
import requests
import torch

# load the processor
processor = AutoProcessor.from_pretrained(
    'allenai/Molmo-72B-0924',
    trust_remote_code=True,
    torch_dtype='auto',
    device_map='auto'
)

# load the model
model = AutoModelForCausalLM.from_pretrained(
    'allenai/Molmo-72B-0924',
    trust_remote_code=True,
    torch_dtype='auto',
    device_map='auto'
)

# process the image and text
inputs = processor.process(
    images=[Image.open(requests.get("https://picsum.photos/id/237/536/354", stream=True).raw)],
    text="Describe this image."
)

# move inputs to the correct device and make a batch of size 1
inputs = {k: v.to(model.device).unsqueeze(0) for k, v in inputs.items()}

# generate output; maximum 200 new tokens; stop generation when <|endoftext|> is generated
output = model.generate_from_batch(
    inputs,
    GenerationConfig(max_new_tokens=200, stop_strings="<|endoftext|>"),
    tokenizer=processor.tokenizer
)

# only get generated tokens; decode them to text
generated_tokens = output[0,inputs['input_ids'].size(1):]
generated_text = processor.tokenizer.decode(generated_tokens, skip_special_tokens=True)

# print the generated text
print(generated_text)

# >>> This image features an adorable black Labrador puppy sitting on a wooden deck. 
#     The puppy is positioned in the center of the frame, looking up at the camera...

To make inference more efficient, run with autocast:

python

with torch.autocast(device_type="cuda", enabled=True, dtype=torch.bfloat16):
  output = model.generate_from_batch(
      inputs,
      GenerationConfig(max_new_tokens=200, stop_strings="<|endoftext|>"),
      tokenizer=processor.tokenizer
  )

We did most of our evaluation in this setting (autocast on, but float32 weights)

To even further reduce the memory requirements, the model can be run with bfloat16 weights:

model.to(dtype=torch.bfloat16)
inputs["images"] = inputs["images"].to(torch.bfloat16)
output = model.generate_from_batch(
    inputs,
    GenerationConfig(max_new_tokens=200, stop_strings="<|endoftext|>"),
    tokenizer=processor.tokenizer
)

Note that we have observed that this can change the output of the model compared to running with float32 weights.

vLLM

Molmo is supported in vLLM, however please use version <=0.7.2 until a prepreprocessing bug is fixed.

Evaluations

Model	Average Score on 11 Academic Benchmarks	Human Preference Elo Rating
Molmo 72B (this model)	81.2	1077
Molmo 7B-D	77.3	1056
Molmo 7B-O	74.6	1051
MolmoE 1B	68.6	1032
GPT-4o	78.5	1079
GPT-4V	71.1	1041
Gemini 1.5 Pro	78.3	1074
Gemini 1.5 Flash	75.1	1054
Claude 3.5 Sonnet	76.7	1069
Claude 3 Opus	66.4	971
Claude 3 Haiku	65.3	999
Qwen VL2 72B	79.4	1037
Qwen VL2 7B	73.7	1025
Intern VL2 LLAMA 76B	77.1	1018
Intern VL2 8B	69.4	953
Pixtral 12B	69.5	1016
Phi3.5-Vision 4B	59.7	982
PaliGemma 3B	50.0	937
LLAVA OneVision 72B	76.6	1051
LLAVA OneVision 7B	72.0	1024
Cambrian-1 34B	66.8	953
Cambrian-1 8B	63.4	952
xGen - MM - Interleave 4B	59.5	979
LLAVA-1.5 13B	43.9	960
LLAVA-1.5 7B	40.7	951

Benchmarks: AI2D test, ChartQA test, VQA v2.0 test, DocQA test, InfographicVQA test, TextVQA val, RealWorldQA, MMMU val, MathVista testmini, CountBenchQA, Flickr Count (we collected this new dataset that is significantly harder than CountBenchQA).

FAQs

I'm getting an error a broadcast error when processing images!

Your image might not be in RGB format. You can convert it using the following code snippet:

python

from PIL import Image

image = Image.open(...)

if image.mode != "RGB":
    image = image.convert("RGB")

Molmo doesn't work great with transparent images!

We received reports that Molmo models might struggle with transparent images. For the time being, we recommend adding a white or dark background to your images before passing them to the model. The code snippet below shows how to do this using the Python Imaging Library (PIL):

python

# Load the image
url = "..."
image = Image.open(requests.get(url, stream=True).raw)

# Convert the image to grayscale to calculate brightness
gray_image = image.convert('L')  # Convert to grayscale

# Calculate the average brightness
stat = ImageStat.Stat(gray_image)
average_brightness = stat.mean[0]  # Get the average value

# Define background color based on brightness (threshold can be adjusted)
bg_color = (0, 0, 0) if average_brightness > 127 else (255, 255, 255)

# Create a new image with the same size as the original, filled with the background color
new_image = Image.new('RGB', image.size, bg_color)

# Paste the original image on top of the background (use image as a mask if needed)
new_image.paste(image, (0, 0), image if image.mode == 'RGBA' else None)

# Now you can pass the new_image to Molmo
processor = AutoProcessor.from_pretrained(
    'allenai/Molmo-7B-D-0924',
    trust_remote_code=True,
    torch_dtype='auto',
    device_map='auto'
)

License and Use

This model is licensed under Apache 2.0. It is intended for research and educational use. For more information, please see our Responsible Use Guidelines. The base model used is Qwen2-72B, whose license (the Tongyi Qianwen license) you can find here.