Model reference · open weights
Olmo-3.1 is an open-weight language model from allenai. AxForge deploys and operates it for you on dedicated EU-owned hardware — with the licence handled where one is required.
Available as managed deployment — configured and operated for you on dedicated EU hardware, quoted per deployment.
What it is
| Maker | allenai |
|---|---|
| Type | Language models |
| Task | Text gen |
| Parameters (lead) | 32.2B |
| Context | 64k tokens |
| Runs with | transformers |
| Based on | allenai/Olmo-3.1-32B-Instruct-DPO |
| Released | 2025-12-10 |
| Popularity | 15k downloads / month |
| Licence | Open weights |
About
We introduce Olmo 3, a new family of 7B and 32B models both Instruct and Think variants. Long chain-of-thought thinking improves reasoning tasks like math and coding.
Olmo is a series of Open language models designed to enable the science of language models. These models are pre-trained on the Dolma 3 dataset and post-trained on the Dolci datasets. We are releasing all code, checkpoints, logs (coming soon), and associated training details.
The core models released in this batch include the following:
| Stage | Olmo 3 7B Think | Olmo (3/3.1) 32B Think | Olmo 3 7B Instruct | Olmo 3.1 32B Instruct |
|---|---|---|---|---|
| Base Model | Olmo-3-7B | Olmo-3-32B | Olmo-3-7B | Olmo-3-32B |
| SFT | Olmo-3-7B-Think-SFT | Olmo-3-32B-Think-SFT | Olmo-3-7B-Instruct-SFT | Olmo-3.1-32B-Instruct-SFT |
| DPO | Olmo-3-7B-Think-DPO | Olmo-3-32B-Think-DPO | Olmo-3-7B-Instruct-DPO | Olmo-3.1-32B-Instruct-DPO |
| Final Models (RLVR) | Olmo-3-7B-Think | Olmo-3-32B-ThinkOlmo-3.1-32B-Think | Olmo-3-7B-Instruct | Olmo-3.1-32B-Instruct |
Olmo 3 is supported in transformers 4.57.0 or higher:
pip install transformers>=4.57.0
You can use OLMo with the standard HuggingFace transformers library:
from transformers import AutoModelForCausalLM, AutoTokenizer
olmo = AutoModelForCausalLM.from_pretrained("allenai/Olmo-3.1-32B-Instruct")
tokenizer = AutoTokenizer.from_pretrained("allenai/Olmo-3.1-32B-Instruct")
message = ["Language modeling is "]
inputs = tokenizer(message, return_tensors='pt', return_token_type_ids=False)
# optional verifying cuda
# inputs = {k: v.to('cuda') for k,v in inputs.items()}
# olmo = olmo.to('cuda')
response = olmo.generate(**inputs, max_new_tokens=100, do_sample=True, top_k=50, top_p=0.95)
print(tokenizer.batch_decode(response, skip_special_tokens=True)[0])
>> 'Language modeling is a key component of any text-based application, but its effectiveness...'
For faster performance, you can quantize the model using the following method:
AutoModelForCausalLM.from_pretrained("allenai/Olmo-3.1-32B-Instruct",
torch_dtype=torch.float16,
load_in_8bit=True) # Requires bitsandbytes
The quantized model is more sensitive to data types and CUDA operations. To avoid potential issues, it's recommended to pass the inputs directly to CUDA using:
inputs.input_ids.to('cuda')
We have released checkpoints for these models. For post-training, the naming convention is step_XXXX.
NOTE: For this model, due to a checkpointing issue, we only are releasing the final few checkpoints. See our other RL jobs for more detailed intermediate checkpoint suite.
To load a specific model revision with HuggingFace, simply add the argument revision:
olmo = AutoModelForCausalLM.from_pretrained("allenai/Olmo-3.1-32B-Instruct", revision="step_1375")
Or, you can access all the revisions for the models via the following code snippet:
from huggingface_hub import list_repo_refs
out = list_repo_refs("allenai/Olmo-3.1-32B-Instruct")
branches = [b.name for b in out.branches]
Model fine-tuning can be done from the final checkpoint (the main revision of this model) or many intermediate checkpoints. Two recipes for tuning are available.
torchrun --nproc-per-node=8 ./src/scripts/official/MODEL.py run01
You can override most configuration options from the command-line. For example, to override the learning rate you could launch the script like this:
torchrun --nproc-per-node=8 ./src/scripts/train/MODEL.py run01 --train_module.optim.lr=6e-3
For more documentation, see the GitHub readme.
olmo@allenai.org. Press: press@allenai.org| Metric | Olmo 3.1 32B Instruct SFT | Olmo 3.1 32B Instruct DPO | Olmo 3.1 32B Instruct | Apertus 70B | Qwen 3 32B (No Think) | Qwen 3 VL 32B Instruct | Qwen 2.5 32B | Gemma 3 27B | Gemma 2
From the published model card. Full card on the HuggingFace links in the sidebar.
Using it via the API
Once AxForge deploys olmo-3-1 for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (olmo-3-1 below is illustrative; you get the exact model name on deployment.)
$ curl -sS https://api.axforge.ai/v1/chat/completions \
-H "Authorization: Bearer $AXFORGE_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"olmo-3-1","messages":[{"role":"user","content":"Hello"}]}'
Create an account — your API key is available in the console. 5M tokens/month currently included with every new account at launch.