GPT-5.6 Luna vs Llama 3.1 405B
Pricing verdict: GPT-5.6 Luna vs Llama 3.1 405B: GPT-5.6 Luna is cheaper for input-heavy usage ($1.00/M vs $3.50/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
Llama 3.1 405B
Cost Differences
Llama 3.1 405B 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 $3.75/month ($45.625/year) versus Llama 3.1 405B.
Feature Comparison
| Feature | GPT-5.6 Luna | Llama 3.1 405B |
|---|---|---|
| Provider | OpenAI | Meta (via Together AI) |
| Input Price | $1.00/1M tokens | $3.50/1M tokens |
| Output Price | $6.00/1M tokens | $3.50/1M tokens |
| Context Window | 1,050,000 tokens | 128,000 tokens |
| Max Output | 128,000 tokens | 32,768 tokens |
| Category | efficient | flagship |
| Capabilities | textvisioncodereasoning | textcodereasoning |
| Release Date | 6/26/2026 | 7/23/2024 |
GPT-5.6 Luna vs Llama 3.1 405B: Which Should You Choose?
Choosing between GPT-5.6 Luna and Llama 3.1 405B 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 — 71% cheaper than Llama 3.1 405B. Meanwhile, GPT-5.6 Luna offers a significantly larger context window at 1,050,000 tokens vs 128,000 for Llama 3.1 405B.
These models come from different providers — OpenAI and Meta (via Together AI) — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with OpenAI, switching to Meta (via Together AI)involves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
These models target different tiers: GPT-5.6 Luna is a efficient model while Llama 3.1 405B is flagship. This means they're optimized for different workloads. Llama 3.1 405B 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 $3.50 for Llama 3.1 405B. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Llama 3.1 405B has the edge here at $3.50/1M output tokens.
Multimodal capabilities: GPT-5.6 Luna supports vision (image inputs) while Llama 3.1 405B 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 need longer outputs (up to 128,000 tokens)
- • You're already using OpenAI's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Choose Llama 3.1 405B when:
- • You're already using Meta (via Together AI)'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
- • Higher output cost than Llama 3.1 405B
Llama 3.1 405B
- • Input pricing: $3.50/M tokens
- • Output pricing: $3.50/M tokens
- • Context window: 128,000 tokens
- • Max output: 32,768 tokens
Watch out for
- • Higher input 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)
Llama 3.1 405B (Meta (via Together AI))
Start using GPT-5.6 Luna today
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Sign Up for Meta (via Together AI) →Frequently Asked Questions
Which is cheaper, GPT-5.6 Luna or Llama 3.1 405B?▼
What is the context window difference between GPT-5.6 Luna and Llama 3.1 405B?▼
Which model is better for AI Agent / Agentic Workflows?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare OpenAI and Meta (via Together AI) API pricing beyond this model matchup?▼
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