Model reference · open weights

circuit-sparsity

LLMs openai Text gen 1 build Open weights 465 dl/mo

circuit-sparsity is an open-weight language model from OpenAI. circuit-sparsity (FP32) weighs 838 MB; the smallest configuration that runs it is RTX 3060 12 GB.

For self-hosting, compare this build's requirements below with the GPU you plan to rent.

  • circuit-sparsity is a 419M parameter text-generation model developed by OpenAI and published as openai/circuit-sparsity.
  • It is a sparse model from Gao et al. 2025, used for qualitative results related to bracket counting and variable binding.
  • The model is licensed under the Apache License 2.0.

Summary of the openai/circuit-sparsity model card, 2026-10-01

What it is

Released byOpenAI
Released2025-12-11
Parameters419M
VRAM838 MB for the weights

What it runs on

Memory and cards for circuit-sparsity (FP32)

838 MBweights, file size
66 MBcache per 1K tokens
532 MBruntime overhead, at least
1,024 tokenscontext max
CardRequests at onceContext maxMemory
1K each
RTX 3060 12 GB152all 1K11.6 GB
RTX 4060 Ti 16 GB209all 1K15.4 GB
RTX 3090 24 GB328all 1K23.4 GB
RTX 4090 24 GB327all 1K23.4 GB
RTX 5090 32 GB441all 1K31.0 GB
L40S 48 GB634all 1K44.0 GB
A100 80 GB1000+all 1K78.2 GB
H100 80 GB1000+all 1K78.1 GB
RTX PRO 6000 Blackwell 96 GB1000+all 1K93.8 GB
DGX Spark (GB10) 128 GB unified1000+all 1K107 GB
H200 141 GB1000+all 1K138 GB
B200 180 GB1000+all 1K176 GB
Memory needed at each load
Requests at once1K tokens each
11.4 GB
51.7 GB
81.9 GB
162.4 GB
323.5 GB
645.7 GB

One card, with vLLM's small-card settings.

From the model card

What OpenAI says about circuit-sparsity

Read the model card

Sparse Model from Gao et al. 2025

Weights for a sparse model from Gao et al. 2025, used for the qualitative results from the paper (related to bracket counting and variable binding). All weights for the other models used in the paper, as well as lightweight inference code, are present in https://github.com/openai/circuit_sparsity. In the context of that repo, this model is csp_yolo2.

This is a runnable standalone huggingface implementation for one of the models. It includes code to load the locally converted HF model + tokenizer and run a tiny generation.

import torch
from transformers import AutoModelForCausalLM, AutoTokenizer

if __name__ == "__main__":
    PROMPT = "def square_sum(xs):\n    return sum(x * x for x in xs)\n\nsquare_sum([1, 2, 3])\n"
    tok = AutoTokenizer.from_pretrained("openai/circuit-sparsity", trust_remote_code=True)
    model = AutoModelForCausalLM.from_pretrained(
        "openai/circuit-sparsity",
        trust_remote_code=True,
        torch_dtype="auto",
    )
    model.to("cuda" if torch.cuda.is_available() else "cpu")
    inputs = tok(PROMPT, return_tensors="pt", add_special_tokens=False)["input_ids"].to(
        model.device
    )

    with torch.no_grad():
        out = model.generate(
            inputs,
            max_new_tokens=64,
            do_sample=True,
            temperature=0.8,
            top_p=0.95,
            return_dict_in_generate=False,
        )

    print("=== Prompt ===")
    print(PROMPT)
    print("\n=== Generation ===")
    print(tok.decode(out[0], skip_special_tokens=True))

License

This project is licensed under the Apache License 2.0.

Quoted from the model card on Hugging Face. The full card is behind the Hugging Face link above.

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