GPT-5.6 Luna vs o3-pro
Pricing verdict: GPT-5.6 Luna vs o3-pro: GPT-5.6 Luna is cheaper for input-heavy usage ($1.00/M vs $20.00/M input tokens), while GPT-5.6 Luna is better for long-context tasks (1,050,000 tokens).
Direct answer: choose GPT-5.6 Luna for lower token spend and choose GPT-5.6 Luna when your workload needs longer context.
Compare API pricing, input and output token costs, context windows, and monthly estimates on one page so you can pick the right model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
GPT-5.6 Luna
o3-pro
Cost Differences
o3-pro costs more than GPT-5.6 Luna
Quick Recommendation
Winner for direct API pricing: GPT-5.6 Luna. At the default workload, GPT-5.6 Luna saves about $168.00/month ($2,044.00/year) versus o3-pro.
Feature Comparison
| Feature | GPT-5.6 Luna | o3-pro |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Input Price | $1.00/1M tokens | $20.00/1M tokens |
| Output Price | $6.00/1M tokens | $80.00/1M tokens |
| Context Window | 1,050,000 tokens | 1,000,000 tokens |
| Max Output | 128,000 tokens | 131,072 tokens |
| Category | efficient | reasoning |
| Capabilities | textvisioncodereasoning | textreasoningcode |
| Release Date | 6/26/2026 | 6/10/2025 |
GPT-5.6 Luna vs o3-pro: Which Should You Choose?
Choosing between GPT-5.6 Luna and o3-pro depends on your priorities: cost efficiency, context length, or raw capability. GPT-5.6 Luna is the more affordable option at $1.00/1M input tokens — 95% cheaper than o3-pro. Meanwhile, GPT-5.6 Luna offers a significantly larger context window at 1,050,000 tokens vs 1,000,000 for o3-pro.
These models target different tiers: GPT-5.6 Luna is a efficient model while o3-pro is reasoning. This means they're optimized for different workloads. o3-pro targets more demanding workloads, while GPT-5.6 Luna provides a cost-effective option for everyday tasks.
Output costs matter too. GPT-5.6 Luna charges $6.00/1M output tokens vs $80.00 for o3-pro. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. GPT-5.6 Luna has the edge here at $6.00/1M output tokens.
Multimodal capabilities: GPT-5.6 Luna supports vision (image inputs) while o3-pro is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose GPT-5.6 Luna when:
- • Budget is a primary concern
- • You need a larger context window (1,050,000 tokens)
- • You need more capabilities (vision)
- • You're already using OpenAI's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Choose o3-pro when:
- • You need longer outputs (up to 131,072 tokens)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
GPT-5.6 Luna
- • Input pricing: $1.00/M tokens
- • Output pricing: $6.00/M tokens
- • Context window: 1,050,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Trade-offs are minor in this matchup.
o3-pro
- • Input pricing: $20.00/M tokens
- • Output pricing: $80.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 131,072 tokens
Watch out for
- • Higher input cost than GPT-5.6 Luna
- • Higher output cost than GPT-5.6 Luna
- • Smaller context window than GPT-5.6 Luna
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
GPT-5.6 Luna (OpenAI)
o3-pro (OpenAI)
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Which is cheaper, GPT-5.6 Luna or o3-pro?▼
What is the context window difference between GPT-5.6 Luna and o3-pro?▼
Which model is better for AI Agent / Agentic Workflows?▼
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