Model specification · OpenAI

gpt-oss-20b

openai/gpt-oss-20b

gpt-oss-20b is an open-weight 21B parameter model released by OpenAI under the Apache 2.0 license. It uses a Mixture-of-Experts (MoE) architecture with 3.6B active parameters per forward pass, optimized for...

SpecificationsReported values
Context window
131K
Maximum output
131K
Architecture
text->text
Tokenizer
GPT
Knowledge cutoff
2024-06-30
Moderated
No
Input modalities
text
Output modalities
text
Full pricingUSD where reported
PriceStandardfree
Input$0.030 / Mfree / M
Output$0.130 / Mfree / M
Benchmark indexesReported indexes
Intelligence
14.9
Coding
20.7
Agentic
3.1
Design Arena Elo
919
Example workload costsStandard pricing only
WorkloadInput / outputCache shareEstimated cost
Quick check10K / 1K × 10%$0.00043
Long analysis100K / 4K × 150%$0.00352
Workday20K / 2K × 1,00030%$0.860
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