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GPT OSS 20B High vs Mercury 2

GPT OSS 20B High significantly outperforms across most benchmarks. GPT OSS 20B High is 1.9x cheaper per token.

OpenAI · Inception · Updated for 2026

Which is better?

GPT OSS 20B High outperforms in 2 benchmarks (AIME 2025, GPQA), while Mercury 2 is better at 0 benchmarks. GPT OSS 20B High significantly outperforms across most benchmarks.

On price, GPT OSS 20B High is roughly 1.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

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

Based on current benchmark, pricing, and model metadata for 2026.

Choose GPT OSS 20B High

  • you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
  • cost matters — it's about 1.9x cheaper per token
  • you process long inputs — it offers a 131,072 token context window
  • you need open weights you can self-host or fine-tune

Choose Mercury 2

  • you want the most recent training data — it shipped Feb 2026

At a glance

The differences that matter most.

Benchmark wins
2 of 2
0 of 2
Input price
$0.10 / M
$0.25 / M
Output price
$0.50 / M
$0.75 / M
Context window
131,072
128,000
Released
Aug 2025
Feb 2026
License
Apache 2.0
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

GPT OSS 20B High outperforms in 2 benchmarks (AIME 2025, GPQA), while Mercury 2 is better at 0 benchmarks.

GPT OSS 20B High significantly outperforms across most benchmarks.

Tue Aug 25 2026 • llm-stats.com

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

GPT OSS 20B High costs less

For input processing, GPT OSS 20B High ($0.10/1M tokens) is 2.5x cheaper than Mercury 2 ($0.25/1M tokens).

For output processing, GPT OSS 20B High ($0.50/1M tokens) is 1.5x cheaper than Mercury 2 ($0.75/1M tokens).

In conclusion, Mercury 2 is more expensive than GPT OSS 20B High.*

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

Lowest available price from all providers
Tue Aug 25 2026 • llm-stats.com
OpenAI
GPT OSS 20B High
Input tokens$0.10
Output tokens$0.50
Best providerOpenAI
Inception
Mercury 2
Input tokens$0.25
Output tokens$0.75
Best providerInception
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT OSS 20B High accepts 131,072 input tokens compared to Mercury 2's 128,000 tokens. GPT OSS 20B High can generate longer responses up to 131,072 tokens, while Mercury 2 is limited to 8,192 tokens.

OpenAI
GPT OSS 20B High
Input131,072 tokens
Output131,072 tokens
Inception
Mercury 2
Input128,000 tokens
Output8,192 tokens
Tue Aug 25 2026 • llm-stats.com

License

Usage and distribution terms

GPT OSS 20B High is licensed under Apache 2.0, while Mercury 2 uses a proprietary license.

License differences may affect how you can use these models in commercial or open-source projects.

GPT OSS 20B High

Apache 2.0

Open weights

Mercury 2

Proprietary

Closed source

Release Timeline

When each model was launched

GPT OSS 20B High was released on 2025-08-05, while Mercury 2 was released on 2026-02-24.

Mercury 2 is 7 months newer than GPT OSS 20B High.

GPT OSS 20B High

Aug 5, 2025

1.1 years ago

Mercury 2

Feb 24, 2026

6 months ago

6mo newer

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 High is available from OpenAI. Mercury 2 is available from Inception.

GPT OSS 20B High

openai logo
OpenAI
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M

Mercury 2

inception logo
Inception
Input Price:Input: $0.25/1MOutput Price:Output: $0.75/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against GPT OSS 20B High and Mercury 2 side-by-side, then vote on the output you prefer.

GPT OSS 20B High
✓ Preferred
Mercury 2
Open in Playground

FAQ

Common questions about GPT OSS 20B High vs Mercury 2.

Which is better, GPT OSS 20B High or Mercury 2?

GPT OSS 20B High significantly outperforms across most benchmarks. GPT OSS 20B High is made by OpenAI and Mercury 2 is made by Inception. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT OSS 20B High compare to Mercury 2 in benchmarks?

GPT OSS 20B High scores AIME 2025: 98.7%, GPQA: 74.2%. Mercury 2 scores AIME 2025: 91.1%, GPQA: 74.0%, IFBench: 71.0%, LiveCodeBench: 67.0%, Tau2 Airline: 53.0%.

Is GPT OSS 20B High cheaper than Mercury 2?

GPT OSS 20B High is 2.5x cheaper for input tokens. GPT OSS 20B High costs $0.10/M input and $0.50/M output via openai. Mercury 2 costs $0.25/M input and $0.75/M output via inception.

What are the context window sizes for GPT OSS 20B High and Mercury 2?

GPT OSS 20B High supports 131K tokens and Mercury 2 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 High and Mercury 2?

Key differences include context window (131K vs 128K), input pricing ($0.10 vs $0.25/M), licensing (Apache 2.0 vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT OSS 20B High and Mercury 2?

GPT OSS 20B High is developed by OpenAI and Mercury 2 is developed by Inception.