Model Comparison

GPT OSS 20B vs Mistral NeMo InstructWhich is better in 2026?

GPT OSS 20B significantly outperforms across most benchmarks. GPT OSS 20B is 1.7x cheaper per token.

Verdict: GPT OSS 20B vs Mistral NeMo Instruct — which is better?

GPT OSS 20B (by OpenAI) and Mistral NeMo Instruct (by Mistral AI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

GPT OSS 20B outperforms in 1 benchmarks (MMLU), while Mistral NeMo Instruct is better at 0 benchmarks. GPT OSS 20B significantly outperforms across most benchmarks.

On price, GPT OSS 20B is roughly 1.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT OSS 20B also accepts a larger context window (131,072 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT OSS 20B if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • cost matters — it's about 1.7x cheaper per token
  • you process long inputs — it offers a 131,072 token context window
  • you want the most recent training data — it shipped Aug 2025

Choose Mistral NeMo Instruct if…

  • you want predictable pricing at $0.15/M input and $0.15/M output
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Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

GPT OSS 20B outperforms in 1 benchmarks (MMLU), while Mistral NeMo Instruct is better at 0 benchmarks.

GPT OSS 20B significantly outperforms across most benchmarks.

Fri Jun 19 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT OSS 20B costs less

For input processing, GPT OSS 20B ($0.05/1M tokens) is 3.0x cheaper than Mistral NeMo Instruct ($0.15/1M tokens).

For output processing, GPT OSS 20B ($0.20/1M tokens) is 1.3x more expensive than Mistral NeMo Instruct ($0.15/1M tokens).

In conclusion, Mistral NeMo Instruct is more expensive than GPT OSS 20B.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Jun 19 2026 • llm-stats.com
OpenAI
GPT OSS 20B
Input tokens$0.05
Output tokens$0.20
Best providerNovita
Mistral AI
Mistral NeMo Instruct
Input tokens$0.15
Output tokens$0.15
Best providerGoogle
Notice missing or incorrect data?Start an Issue→

Model Size

Parameter count comparison

8.9B diff

GPT OSS 20B has 8.9B more parameters than Mistral NeMo Instruct, making it 74.2% larger.

OpenAI
GPT OSS 20B
20.9Bparameters
Mistral AI
Mistral NeMo Instruct
12.0Bparameters
20.9B
GPT OSS 20B
12.0B
Mistral NeMo Instruct

Context Window

Maximum input and output token capacity

GPT OSS 20B accepts 131,072 input tokens compared to Mistral NeMo Instruct's 128,000 tokens. Mistral NeMo Instruct can generate longer responses up to 128,000 tokens, while GPT OSS 20B is limited to 32,768 tokens.

OpenAI
GPT OSS 20B
Input131,072 tokens
Output32,768 tokens
Mistral AI
Mistral NeMo Instruct
Input128,000 tokens
Output128,000 tokens
Fri Jun 19 2026 • llm-stats.com

License

Usage and distribution terms

Both models are licensed under Apache 2.0.

Both models share the same licensing terms, providing consistent usage rights.

GPT OSS 20B

Apache 2.0

Open weights

Mistral NeMo Instruct

Apache 2.0

Open weights

Release Timeline

When each model was launched

GPT OSS 20B was released on 2025-08-05, while Mistral NeMo Instruct was released on 2024-07-18.

GPT OSS 20B is 13 months newer than Mistral NeMo Instruct.

GPT OSS 20B

Aug 5, 2025

10 months ago

1.0yr newer
Mistral NeMo Instruct

Jul 18, 2024

1.9 years ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

GPT OSS 20B is available from Novita, Fireworks, Groq, OpenAI. Mistral NeMo Instruct is available from Google, Mistral AI.

GPT OSS 20B

novita logo
Novita
Input Price:Input: $0.05/1MOutput Price:Output: $0.20/1M
fireworks logo
Fireworks
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M
groq logo
Groq
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M
openai logo
OpenAI
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M

Mistral NeMo Instruct

google logo
Google
Input Price:Input: $0.15/1MOutput Price:Output: $0.15/1M
mistral logo
Mistral
Input Price:Input: $0.15/1MOutput Price:Output: $0.15/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI
Larger context window (131,072 tokens)
Less expensive input tokens
Higher MMLU score (85.3% vs 68.0%)
Mistral AI
Less expensive output tokens

Detailed Comparison

AI Model Comparison Table
Feature
OpenAI
GPT OSS 20B
Mistral AI
Mistral NeMo Instruct

FAQ

Common questions about GPT OSS 20B vs Mistral NeMo Instruct.

Which is better, GPT OSS 20B or Mistral NeMo Instruct?

GPT OSS 20B significantly outperforms across most benchmarks. GPT OSS 20B is made by OpenAI and Mistral NeMo Instruct is made by Mistral AI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT OSS 20B compare to Mistral NeMo Instruct in benchmarks?

GPT OSS 20B scores MMLU: 85.3%, CodeForces: 74.3%, GPQA: 71.5%, TAU-bench Retail: 54.8%, HealthBench: 42.5%. Mistral NeMo Instruct scores HellaSwag: 83.5%, Winogrande: 76.8%, TriviaQA: 73.8%, CommonSenseQA: 70.4%, MMLU: 68.0%.

Is GPT OSS 20B cheaper than Mistral NeMo Instruct?

GPT OSS 20B is 3.0x cheaper for input tokens. GPT OSS 20B costs $0.05/M input and $0.20/M output via novita. Mistral NeMo Instruct costs $0.15/M input and $0.15/M output via google.

What are the context window sizes for GPT OSS 20B and Mistral NeMo Instruct?

GPT OSS 20B supports 131K tokens and Mistral NeMo Instruct supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT OSS 20B and Mistral NeMo Instruct?

Key differences include context window (131K vs 128K), input pricing ($0.05 vs $0.15/M). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT OSS 20B and Mistral NeMo Instruct?

GPT OSS 20B is developed by OpenAI and Mistral NeMo Instruct is developed by Mistral AI.

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