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GPT-5 mini vs Mercury 2

GPT-5 mini has a slight edge in benchmark performance. Mercury 2 is 1.8x cheaper per token.

OpenAI · Inception · Updated for 2026

Which is better?

GPT-5 mini outperforms in 1 benchmarks (GPQA), while Mercury 2 is better at 0 benchmarks. GPT-5 mini has a slight edge in benchmark performance.

On price, Mercury 2 is roughly 1.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5 mini also accepts a larger context window (400,000 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-5 mini

  • you process long inputs — it offers a 400,000 token context window

Choose Mercury 2

  • cost matters — it's about 1.8x cheaper per token
  • you want the most recent training data — it shipped Feb 2026

At a glance

The differences that matter most.

Benchmark wins
1 of 2
1 of 2
Input price
$0.25 / M
$0.25 / M
Output price
$2.00 / M
$0.75 / M
Context window
400,000
128,000
Released
Aug 2025
Feb 2026
License
Proprietary
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

GPT-5 mini outperforms in 1 benchmarks (GPQA), while Mercury 2 is better at 0 benchmarks.

GPT-5 mini has a slight edge in benchmark performance.

Tue Aug 25 2026 • llm-stats.com

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

Mercury 2 costs less

For input processing, GPT-5 mini ($0.25/1M tokens) costs the same as Mercury 2 ($0.25/1M tokens).

For output processing, GPT-5 mini ($2.00/1M tokens) is 2.7x more expensive than Mercury 2 ($0.75/1M tokens).

In conclusion, GPT-5 mini is more expensive than Mercury 2.*

* 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-5 mini
Input tokens$0.25
Output tokens$2.00
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-5 mini accepts 400,000 input tokens compared to Mercury 2's 128,000 tokens. GPT-5 mini can generate longer responses up to 128,000 tokens, while Mercury 2 is limited to 8,192 tokens.

OpenAI
GPT-5 mini
Input400,000 tokens
Output128,000 tokens
Inception
Mercury 2
Input128,000 tokens
Output8,192 tokens
Tue Aug 25 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5 mini supports multimodal inputs, whereas Mercury 2 does not.

GPT-5 mini can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-5 mini

Text
Images
Audio
Video

Mercury 2

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

GPT-5 mini

Proprietary

Closed source

Mercury 2

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5 mini was released on 2025-08-07, while Mercury 2 was released on 2026-02-24.

Mercury 2 is 7 months newer than GPT-5 mini.

GPT-5 mini

Aug 7, 2025

1.0 years ago

Mercury 2

Feb 24, 2026

6 months ago

6mo newer

Knowledge Cutoff

When training data ends

GPT-5 mini has a documented knowledge cutoff of 2024-05-30, while Mercury 2's cutoff date is not specified.

We can confirm GPT-5 mini's training data extends to 2024-05-30, but cannot make a direct comparison without Mercury 2's cutoff date.

GPT-5 mini

May 2024

Mercury 2

Provider Availability

GPT-5 mini is available from OpenAI. Mercury 2 is available from Inception.

GPT-5 mini

openai logo
OpenAI
Input Price:Input: $0.25/1MOutput Price:Output: $2.00/1M

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-5 mini and Mercury 2 side-by-side, then vote on the output you prefer.

GPT-5 mini
✓ Preferred
Mercury 2
Open in Playground

FAQ

Common questions about GPT-5 mini vs Mercury 2.

Which is better, GPT-5 mini or Mercury 2?

GPT-5 mini has a slight edge in benchmark performance. GPT-5 mini 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-5 mini compare to Mercury 2 in benchmarks?

GPT-5 mini scores AIME 2025: 91.1%, HMMT 2025: 87.8%, GPQA: 82.3%, FrontierMath: 22.1%, Humanity's Last Exam: 16.7%. Mercury 2 scores AIME 2025: 91.1%, GPQA: 74.0%, IFBench: 71.0%, LiveCodeBench: 67.0%, Tau2 Airline: 53.0%.

Is GPT-5 mini cheaper than Mercury 2?

Both models cost $0.25 per million input tokens.

What are the context window sizes for GPT-5 mini and Mercury 2?

GPT-5 mini supports 400K 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-5 mini and Mercury 2?

Key differences include context window (400K vs 128K), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5 mini and Mercury 2?

GPT-5 mini is developed by OpenAI and Mercury 2 is developed by Inception.