Google · Open weights
DiffusionGemma
DiffusionGemma is a high-speed diffusion-based version of Gemma 4 26B A4B. It supports optional reasoning and a 262,144-token context window. Temperature, min-p, seed, minimum output tokens, logit bias, bad words, and allowed token IDs are unavailable; omit these parameters to use native diffusion sampling.
- Reasoning
- Input
- Text
- Output
- Text
- Reasoning effort
- none · xhigh
- Discovery tier
- Open weights
Pricing
USD per 1M tokens- Input
- $0.05
- Output
- $0.15
- Cache read
- $0.025
Reference prices as published by the model provider. API example
Specifications
- Context window
- 262.1K
- Max output
- 32.8K
- Average output (7 days)
- 266 tokens
- Longer than 28% of 473 models
Side by side
DiffusionGemma compared
Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.
| DiffusionGemmaGoogleThis model | Gemma 4 12B Starry OceanGoogleRemove | |
|---|---|---|
| Provider | ||
| Discovery tier | Open weights | Open weights |
| Added | Sep 19, 2026 | Oct 15, 2026 |
| Limits | ||
| Context window | 262.14KBest | 131.07K |
| Max output | 32.77K | — |
| Average output | 266 tokens | 233 tokens |
| Pricing, USD per 1M tokens | ||
| Input | $0.05 | $0.05 |
| Output | $0.15Best | $0.25 |
| Cache read | $0.025 | $0.025 |
| Performance | ||
| Throughput | — | 18.1 tok/s |
| Time to first token | — | 1.8 s |
| Request success (24h) | — | 99.3% |
| Benchmark indexes | ||
| Intelligence Index | 9.5 | — |
| Coding Index | 19.7 | — |
| Capabilities | ||
| Reasoning | Yes | Yes |
| Tools | No | Yes |
| Vision | No | Yes |
| Reasoning effort | none, xhigh | none, high |
Public evaluations
Benchmarks
Independent evaluation results, with how each score ranks among the models in the Noumen catalog.
- DiffusionGemma
- Gemma 4 12B Starry Ocean
Intelligence Index
- DiffusionGemma9.5
- Gemma 4 12B Starry Ocean—
DiffusionGemma: Better than 19% of 326 scored models
Indexes
Coding Index
Composite of the coding evaluations
- DiffusionGemma: 19.7
- Gemma 4 12B Starry Ocean: —
Agentic work
GDPval-AAv2.1
Economically valuable occupational tasks, rated head to head
- DiffusionGemma: 321 Elo
- Gemma 4 12B Starry Ocean: —
Document reasoning
AA-LCRv1.1
Reasoning across long documents
- DiffusionGemma: 19.7%
- Gemma 4 12B Starry Ocean: —
Reasoning and knowledge
Humanity’s Last Exam
Expert-level questions across academic fields
- DiffusionGemma: 10.8%
- Gemma 4 12B Starry Ocean: —
GPQA Diamond
Graduate-level science questions
- DiffusionGemma: 66.9%
- Gemma 4 12B Starry Ocean: —
IFBench
Following precise output instructions
- DiffusionGemma: 59.5%
- Gemma 4 12B Starry Ocean: —
Legacy evaluations
AA-LCR (unversioned)
Long-context reasoning, earlier grading
- DiffusionGemma: 19.7%
- Gemma 4 12B Starry Ocean: —
Scores from Artificial Analysis, updated Oct 26, 2026. Artificial Analysis
Live routing data
Performance and reliability
Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.
- Prompt cache hits
- 0.0%
- About $0.05 per 1M input tokens with caching
Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.
Developers
Use it through the API
Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.
curl https://www.noumen.xyz/api/v1/chat/completions \
-H "Authorization: Bearer $NOUMEN_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "google/diffusiongemma",
"reasoning_effort": "none",
"messages": [{ "role": "user", "content": "Explain this stack trace." }]
}'import os
from openai import OpenAI
client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
model="google/diffusiongemma",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)Related models
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