GPT-5.6 Luna Pro (batch) vs Mercury 2.5 Preview
| Signal | GPT-5.6 Luna Pro (batch) | Delta | Mercury 2.5 Preview |
|---|---|---|---|
Capabilities | 100 | +33 | |
Benchmarks | 88 | +28 | |
Pricing | 99 | 0 | |
Context window size | 96 | +10 | |
Recency | 100 | -- | |
Output Capacity | 82 | +5 | |
| Overall Result | 4 wins | of 6 | 1 wins |
Score History
89
current score
GPT-5.6 Luna Pro (batch)
right now
61.2
current score
GPT-5.6 Luna Pro (batch)
OpenAI
Mercury 2.5 Preview
Inception
Mercury 2.5 Preview saves you $28.50/month
That's $342.00/year compared to GPT-5.6 Luna Pro (batch) at your current usage level of 100K calls/month.
| Metric | GPT-5.6 Luna Pro (batch) | Mercury 2.5 Preview | Winner |
|---|---|---|---|
| Overall Score | 89 | 61 | GPT-5.6 Luna Pro (batch) |
| Rank | #31 | #208 | GPT-5.6 Luna Pro (batch) |
| Quality Rank | #31 | #208 | GPT-5.6 Luna Pro (batch) |
| Adoption Rank | #31 | #208 | GPT-5.6 Luna Pro (batch) |
| Parameters | -- | -- | -- |
| Context Window | 1050K | 260K | GPT-5.6 Luna Pro (batch) |
| Pricing | $0.10/$0.60/M | $0.04/$0.15/M | -- |
| Signal Scores | |||
| Capabilities | 100 | 67 | GPT-5.6 Luna Pro (batch) |
| Benchmarks | 88 | 60 | GPT-5.6 Luna Pro (batch) |
| Pricing | 99 | 100 | Mercury 2.5 Preview |
| Context window size | 96 | 86 | GPT-5.6 Luna Pro (batch) |
| Recency | 100 | 100 | GPT-5.6 Luna Pro (batch) |
| Output Capacity | 82 | 77 | GPT-5.6 Luna Pro (batch) |
Our score (0-100) is driven by benchmark performance (90%) from Arena Elo ratings, MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations. Capabilities and context window serve as tiebreakers (10%). Learn more about our methodology.
Scores 89/100 (rank #31), placing it in the top 90% of all 290 models tracked.
Scores 61/100 (rank #208), placing it in the top 29% of all 290 models tracked.
GPT-5.6 Luna Pro (batch) has a 28-point advantage, which typically translates to noticeably stronger performance on complex reasoning, code generation, and multi-step tasks.
Choose GPT-5.6 Luna Pro (batch) when you need:
- Processing long documents or large codebases (1050K token context)
- Multimodal workflows that require image understanding
- Step-by-step reasoning and chain-of-thought problem solving
Choose Mercury 2.5 Preview when you need:
- High-volume production workloads where API costs must be minimized
- Step-by-step reasoning and chain-of-thought problem solving
Mercury 2.5 Preview offers 73% better value per quality point. At 1M tokens/day, you'd spend $2.85/month with Mercury 2.5 Preview vs $10.50/month with GPT-5.6 Luna Pro (batch) - a $7.65 monthly difference.
Both models have comparable response speeds. For most applications, the latency difference is negligible.
When latency matters most: Interactive chatbots, IDE code completion, real-time translation, and user-facing applications where response time directly impacts experience. For batch processing, background summarization, or offline analysis, latency is less critical.
Code generation & review
Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring
Customer support chatbot
Suitable for user-facing chat with competitive response times. Mercury 2.5 Preview also offers lower per-token costs for high-volume support
Long document analysis
Larger context window (1050K tokens) can process longer documents, contracts, and research papers in a single pass
Batch data extraction
Lower output pricing ($0.15/M) reduces costs when processing thousands of records daily
Creative writing & content
Higher overall composite score (89/100) correlates with better nuance, coherence, and style in long-form content
Image understanding & OCR
Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly
GPT-5.6 Luna Pro (batch) clearly outperforms Mercury 2.5 Preview with a significant 27.799999999999997-point lead. For most general use cases, GPT-5.6 Luna Pro (batch) is the stronger choice. However, Mercury 2.5 Preview may still excel in niche scenarios.
By Use Case
Best for Quality
GPT-5.6 Luna Pro (batch)
Marginally better benchmark scores; both are excellent
Best for Cost
Mercury 2.5 Preview
73% lower pricing; better value at scale
Best for Reliability
GPT-5.6 Luna Pro (batch)
Higher uptime and faster response speeds
Best for Prototyping
GPT-5.6 Luna Pro (batch)
Stronger community support and better developer experience
Best for Production
GPT-5.6 Luna Pro (batch)
Wider enterprise adoption and proven at scale
by OpenAI
- Choose for Quality - Marginally better benchmark scores; both are excellent
- Choose for Reliability - Higher uptime and faster response speeds
- Choose for Prototyping - Stronger community support and better developer experience
- Choose for Production - Wider enterprise adoption and proven at scale
| Capability | GPT-5.6 Luna Pro (batch) | Mercury 2.5 Preview |
|---|---|---|
| Vision (Image Input)differs | ||
| Function Calling | ||
| Streaming | ||
| JSON Mode | ||
| Reasoning | ||
| Web Searchdiffers | ||
| Image Output |
GPT-5.6 Luna Pro (batch)
OpenAI
Mercury 2.5 Preview
Inception
Mercury 2.5 Preview saves you $0.6480/month
That's 72% cheaper than GPT-5.6 Luna Pro (batch) at 1,000 tokens/request and 100 requests/day.
Assumes 60% input / 40% output token ratio per request. Actual costs may vary based on your usage pattern.
| Parameter | GPT-5.6 Luna Pro (batch) | Mercury 2.5 Preview |
|---|---|---|
| Context Window | 1.1M | 260K |
| Max Output Tokens | 128,000 | 65,536 |
| Open Source | No | No |
| Created | Jul 9, 2026 | Aug 31, 2026 |