Where is the gpt-oss-120b documentation?

The gpt-oss-120b documentation on OpenRouter includes the LLM Quantization: What fp8 and fp4 Do to Quality and Price blog post. The quickstart covers API keys and your first request, and the API reference lists every parameter.

How much does gpt-oss-120b cost?

gpt-oss-120b costs $0.03/M input tokens and $0.15/M output tokens, with separate rates for Cache Read at $0.015/M tokens.

What is the context length of gpt-oss-120b?

gpt-oss-120b has a 131,072 token context window. It supports up to 131,072 completion tokens.

Does gpt-oss-120b support tool calling and structured outputs?

Yes. gpt-oss-120b accepts tools and tool_choice for function calling on 19 of the 22 providers serving it, and requests that send tools are routed to those providers. It also supports structured outputs via a JSON schema in response_format.

Which providers serve gpt-oss-120b?

gpt-oss-120b is served by 22 providers on OpenRouter: NEAR AI, Venice, CoreWeave, DekaLLM, AkashML, Prime Intellect, DeepInfra (fp8), Crusoe and 14 more. Requests are routed to the best available provider, with automatic failover to the others, and you can pin or exclude providers with provider routing.

When was gpt-oss-120b released?

gpt-oss-120b was released on August 5, 2025. Its knowledge cutoff is June 30, 2024.

OpenAI: gpt-oss-120b

openai/gpt-oss-120b

Model weights

Compare

gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI designed for high-reasoning, agentic, and general-purpose production use cases. It activates 5.1B parameters per forward pass and is optimized to run on a single H100 GPU with native MXFP4 quantization. The model supports configurable reasoning depth, full chain-of-thought access, and native tool use, including function calling, browsing, and structured output generation.

Modalities

In / out price

$0.03 / $0.15per 1M

Context

131K

Released

Aug 5, 2025

Knowledge cutoff

Jun 2024

Providers

Different companies host the same model. OpenRouter routes your request to one of them based on the routing mode you pick: Balanced (price + speed), Nitro (fastest), or Floor (cheapest).

Latency / throughput


	$0.05	$0.25	$0.05	0.19s	242 tok/s	100.00%
	$0.03	$0.187	$0.03	0.36s	108 tok/s	99.64%
	$0.06	$0.40	$0.03	0.65s	144 tok/s	100.00%
	$0.15	$0.60	$0.075	0.19s	356 tok/s	99.67%
	$0.035	$0.075	$0.031	0.55s	101 tok/s	99.93%
	$0.03	$0.15	$0.015	0.63s	78 tok/s	99.93%
	$0.14	$0.95	--	0.61s	212 tok/s	99.90%
	$0.06	$0.42	$0.012	0.53s	53 tok/s	100.00%
Fast	$0.15	$0.75	--	0.26s	163 tok/s	99.63%
	$0.15	$0.60	$0.075	1.20s	53 tok/s	97.85%
	$0.03	$0.18	$0.03	0.51s	46 tok/s	97.30%
	$0.03	$0.15	$0.03	0.67s	38 tok/s	98.15%
	$0.25	$0.45	$0.085	2.35s	30 tok/s	86.52%
	$0.20	$0.95	--	1.38s	59 tok/s	88.97%
	$0.10	$0.50	$0.10	0.16s	222 tok/s	99.73%
	$0.03	$0.17	$0.03	0.23s	112 tok/s	99.39%
	$0.10	$0.50	$0.10	0.15s	203 tok/s	99.79%
	$0.15	$0.60	--	0.58s	357 tok/s	97.49%
	$0.10	$0.75	$0.055	0.24s	166 tok/s	99.53%
	$0.055	$0.25	$0.055	0.61s	78 tok/s	99.46%
	$0.15	$0.60	--	0.49s	162 tok/s	97.94%
	$0.35	$0.75	$0.35	0.18s	709 tok/s	100.00%
	$0.037	$0.17	--	0.43s	31 tok/s	99.94%
	$0.15	$0.60	$0.10	0.29s	287 tok/s	99.93%
	$0.15	$0.60	--	0.19s	120 tok/s	99.17%
	$0.09	$0.36	--	0.19s	213 tok/s	36.72%

Input $0.05Output $0.25
242 tok/s100.00% uptime
Input $0.03Output $0.187
108 tok/s99.64% uptime
Input $0.06Output $0.40
144 tok/s100.00% uptime
Input $0.15Output $0.60
356 tok/s99.67% uptime
Input $0.035Output $0.075
101 tok/s99.93% uptime
Input $0.03Output $0.15
78 tok/s99.93% uptime
Input $0.14Output $0.95
212 tok/s99.90% uptime
Input $0.06Output $0.42
53 tok/s100.00% uptime
Input $0.15Output $0.75
Fast
163 tok/s99.63% uptime
Input $0.15Output $0.60
53 tok/s97.85% uptime
Input $0.03Output $0.18
46 tok/s97.30% uptime
Input $0.03Output $0.15
38 tok/s98.15% uptime
Input $0.25Output $0.45
30 tok/s86.52% uptime
Input $0.20Output $0.95
59 tok/s88.97% uptime
Input $0.10Output $0.50
222 tok/s99.73% uptime
Input $0.03Output $0.17
112 tok/s99.39% uptime
Input $0.10Output $0.50
203 tok/s99.79% uptime
Input $0.15Output $0.60
357 tok/s97.49% uptime
Input $0.10Output $0.75
166 tok/s99.53% uptime
Input $0.055Output $0.25
78 tok/s99.46% uptime
Input $0.15Output $0.60
162 tok/s97.94% uptime
Input $0.35Output $0.75
709 tok/s100.00% uptime
Input $0.037Output $0.17
31 tok/s99.94% uptime
Input $0.15Output $0.60
287 tok/s99.93% uptime
Input $0.15Output $0.60
120 tok/s99.17% uptime
Input $0.09Output $0.36
213 tok/s36.72% uptime

Pricing

The average price customers actually pay for this model, next to the prices providers post. Caching and discounts mean the price actually paid is often well below the listed one.

Weighted average

Input

$0.08618/M tokens

Output

$0.3425/M tokens

gpt-oss-120b — Price history

Price history

No effective price data for this selection

	$0.0206	$0.1490	61.6%	12.3%
	$0.0297	$0.1798	15.2%	2.0%
	$0.0298	$0.1863	59.6%	9.3%
	$0.0298	$0.1485	58.0%	0.5%
	$0.0300	$0.1689	89.9%	17.4%
	$0.0359	$0.0808	53.1%	2.0%
	$0.0367	$0.1692	0.0%	3.5%
	$0.0422	$0.3994	59.2%	1.4%
	$0.0492	$0.4192	21.7%	0.0%
	$0.0498	$0.2492	52.4%	10.7%
	$0.0542	$0.2486	23.0%	0.0%
	$0.0826	$0.7494	38.5%	0.2%
	$0.0997	$0.5991	66.9%	22.8%
	$0.0999	$0.4994	62.0%	1.3%
	$0.0999	$0.4993	68.3%	0.5%
	$0.1120	$0.5990	75.8%	0.4%
	$0.1399	$0.9489	0.0%	0.3%
	$0.1496	$0.5972	0.0%	0.5%
Fast	$0.1497	$0.7489	34.9%	0.3%
	$0.1498	$0.5995	0.0%	0.0%
	$0.1499	$0.5994	42.8%	0.4%
	$0.1500	$0.5996	0.0%	0.9%
	$0.1998	$0.9462	0.0%	0.6%
	$0.2426	$0.4485	4.4%	0.1%
	$0.3498	$0.7490	66.9%	9.8%
	$0.0898	$0.3589	70.3%	2.8%

Effective in $0.0206Effective out $0.1490
Token share
12.3%
Effective in $0.0297Effective out $0.1798
Token share
2.0%
Effective in $0.0298Effective out $0.1863
Token share
9.3%
Effective in $0.0298Effective out $0.1485
Token share
0.5%
Effective in $0.0300Effective out $0.1689
Token share
17.4%
Effective in $0.0359Effective out $0.0808
Token share
2.0%
Effective in $0.0367Effective out $0.1692
Token share
3.5%
Effective in $0.0422Effective out $0.3994
Token share
1.4%
Effective in $0.0492Effective out $0.4192
Token share
0.0%
Effective in $0.0498Effective out $0.2492
Token share
10.7%
Effective in $0.0542Effective out $0.2486
Token share
0.0%
Effective in $0.0826Effective out $0.7494
Token share
0.2%
Effective in $0.0997Effective out $0.5991
Token share
22.8%
Effective in $0.0999Effective out $0.4994
Token share
1.3%
Effective in $0.0999Effective out $0.4993
Token share
0.5%
Effective in $0.1120Effective out $0.5990
Token share
0.4%
Effective in $0.1399Effective out $0.9489
Token share
0.3%
Effective in $0.1496Effective out $0.5972
Token share
0.5%
Effective in $0.1497Effective out $0.7489
FastToken share
0.3%
Effective in $0.1498Effective out $0.5995
Token share
0.0%
Effective in $0.1499Effective out $0.5994
Token share
0.4%
Effective in $0.1500Effective out $0.5996
Token share
0.9%
Effective in $0.1998Effective out $0.9462
Token share
0.6%
Effective in $0.2426Effective out $0.4485
Token share
0.1%
Effective in $0.3498Effective out $0.7490
Token share
9.8%
Effective in $0.0898Effective out $0.3589
Token share
2.8%

Performance

Throughput is how fast the model writes (tokens per second — higher is better). Latency is total round-trip time (lower is better). TTFT is time-to-first-token — how long before you see anything appear (lower is better).

Throughput

709tok/s

P50, best across providers

Latency

0.15s

P50, best provider

Reasoning effortLatency / throughput

AutoExacto benchmarks

GPQA DiamondTAU-BenchAmazon Bedrock (EU)76.8%--Amazon Bedrock76.4%--Google Vertex74.5%--Parasail (Fast)78.8%68.0%AkashML77.6%66.9%io.net77.2%67.3%Parasail77.1%65.2%

+21 more providers

Uptime

Uptime is the percentage of the past 3 days that at least one provider was responding to requests. Availability is the percentage of time that inference was successfully served. OpenRouter continuously monitors and uses the next-best provider when one returns an error.

Uptime (3d)

100.00%

Availability (3d)

99.15%

Availability over the last 3 days

Last 72 hours

Availability 99.15%

3 Days Ago2 Days AgoYesterdayNow

Availability over the last 24 hours

OpenRouter Availability

99.23%

Without Routing

91.90%

When an error occurs in an upstream provider, we can recover by routing to another healthy provider, if your request filters allow it. You can access per-provider uptime data programmatically through the Endpoints API. Learn more about our load balancing and provider routing options.

Benchmarks

Scores on standardized evaluations and this model’s own outputs on shared benchmark prompts. Higher percentages are better — and each rank shows where this model lands among the models evaluated on that source.

Benchmark score summary for OpenAI: gpt-oss-120b (Artificial Analysis, Design Arena and Vals AI)
Source	Benchmark	Score
Artificial Analysis	gpt-oss-120b (High) Intelligence Index	3.8
Artificial Analysis	gpt-oss-120b (High) Coding Index	30.4
Artificial Analysis	gpt-oss-120b (High) Agentic Index	3.7
Artificial Analysis	gpt-oss-120b (High) GPQA Diamond	78.2%
Artificial Analysis	gpt-oss-120b (High) HLE	19.6%
Artificial Analysis	gpt-oss-120b (High) IFBench	69.0%
Artificial Analysis	gpt-oss-120b (High) τ²-Bench Telecom	65.8%
Artificial Analysis	gpt-oss-120b (High) AA-LCR	52.0%
Artificial Analysis	gpt-oss-120b (High) τ-Bench Banking	12.8%
Artificial Analysis	gpt-oss-120b (High) GDPval-AA	5.8%
Artificial Analysis	gpt-oss-120b (High) CritPt	1.1%
Artificial Analysis	gpt-oss-120b (High) LiveCodeBench	87.8%
Artificial Analysis	gpt-oss-120b (High) SciCode	34.0%
Artificial Analysis	gpt-oss-120b (High) Terminal-Bench Hard	23.5%
Artificial Analysis	gpt-oss-120b (High) Terminal-Bench 4.0	0.0%
Artificial Analysis	gpt-oss-120b (High) Terminal-Bench 2.1	26.2%
Artificial Analysis	gpt-oss-120b (High) MMLU-Pro	80.8%
Artificial Analysis	gpt-oss-120b (High) AA-Omniscience Accuracy	21.7%
Artificial Analysis	gpt-oss-120b (High) AA-Omniscience Non-Hallucination Rate	13.1%
Artificial Analysis	gpt-oss-120b (High) AIME 2025	93.4%
Artificial Analysis	gpt-oss-120b (Low) Coding Index	21.2
Artificial Analysis	gpt-oss-120b (Low) GPQA Diamond	67.2%
Artificial Analysis	gpt-oss-120b (Low) HLE	5.9%
Artificial Analysis	gpt-oss-120b (Low) IFBench	58.3%
Artificial Analysis	gpt-oss-120b (Low) τ²-Bench Telecom	45.0%
Artificial Analysis	gpt-oss-120b (Low) AA-LCR	46.0%
Artificial Analysis	gpt-oss-120b (Low) τ-Bench Banking	2.9%
Artificial Analysis	gpt-oss-120b (Low) GDPval-AA	0.0%
Artificial Analysis	gpt-oss-120b (Low) CritPt	0.0%
Artificial Analysis	gpt-oss-120b (Low) LiveCodeBench	70.7%
Artificial Analysis	gpt-oss-120b (Low) Terminal-Bench Hard	5.3%
Artificial Analysis	gpt-oss-120b (Low) Terminal-Bench 2.1	13.9%
Artificial Analysis	gpt-oss-120b (Low) MMLU-Pro	77.5%
Artificial Analysis	gpt-oss-120b (Low) AIME 2025	66.7%
Design Arena	GPT OSS 120B Models Arena 3D Elo	881
Design Arena	GPT OSS 120B Models Arena Code Categories Elo	952
Design Arena	GPT OSS 120B Models Arena Data Visualization Elo	984
Design Arena	GPT OSS 120B Models Arena Game Development Elo	981
Design Arena	GPT OSS 120B Models Arena UI Component Elo	917
Design Arena	GPT OSS 120B Models Arena Website Elo	960
Vals AI	GPT OSS 120B AIME	92.6%
Vals AI	GPT OSS 120B CaseLaw v2	48.8%
Vals AI	GPT OSS 120B CorpFin v2	58.2%
Vals AI	GPT OSS 120B Finance Agent v1.1	21.5%
Vals AI	GPT OSS 120B GPQA Diamond	78.5%
Vals AI	GPT OSS 120B LiveCodeBench	83.2%
Vals AI	GPT OSS 120B LegalBench	75.9%
Vals AI	GPT OSS 120B MATH 500	94.8%
Vals AI	GPT OSS 120B MedQA	91.4%
Vals AI	GPT OSS 120B MGSM	92.0%
Vals AI	GPT OSS 120B MMLU Pro	79.2%
Vals AI	GPT OSS 120B SWE-bench	33.6%
Vals AI	GPT OSS 120B TaxEval v2	71.6%
Vals AI	GPT OSS 120B Terminal-Bench 2.0	19.1%

Available through EU in-region routing

OpenAI: gpt-oss-120b is available through EU in-region routing. Requests sent to eu.openrouter.ai are decrypted in the EU and routed only to shared provider endpoints in Europe (the EU/EEA, the UK, and Switzerland).

Providers in Europe

Amazon Bedrock

Prices in Europe

Amazon Bedrock: $0.15/M tokens input, $0.60/M tokens output

Base URL

https://eu.openrouter.ai/api/v1

Plan

Requires Business or Enterprise. Self-serve on Business: no contract, no monthly minimum. OpenRouter Business for EU in-region routing

Fails closed: if no shared provider endpoint in Europe is available, the request errors instead of leaving the region. Requests served by your own BYOK key go to your deployment’s region, which you control. In-region routing docs

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OpenAI: gpt-oss-120b

Providers