GPT-5.4 Pro vs Llama 3.1 405B
Compare OpenAI and Meta (via Together AI) AI models
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
GPT-5.4 Pro
Llama 3.1 405B
Cost Differences
Llama 3.1 405B costs less than GPT-5.4 Pro
Feature Comparison
| Feature | GPT-5.4 Pro | Llama 3.1 405B |
|---|---|---|
| Provider | OpenAI | Meta (via Together AI) |
| Input Price | $30.00/1M tokens | $3.50/1M tokens |
| Output Price | $180.00/1M tokens | $3.50/1M tokens |
| Context Window | 1,050,000 tokens | 128,000 tokens |
| Max Output | 131,072 tokens | 32,768 tokens |
| Category | reasoning | flagship |
| Capabilities | textvisioncodereasoning | textcodereasoning |
| Release Date | 3/6/2026 | 7/23/2024 |
GPT-5.4 Pro vs Llama 3.1 405B: Which Should You Choose?
Choosing between GPT-5.4 Pro and Llama 3.1 405B depends on your priorities: cost efficiency, context length, or raw capability. Llama 3.1 405B is the more affordable option at $3.50/1M input tokens — 88% cheaper than GPT-5.4 Pro. Meanwhile, GPT-5.4 Pro 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-5.4 Pro is a reasoning model while Llama 3.1 405B is flagship. This means they're optimized for different workloads. GPT-5.4 Pro is built for complex tasks that require deeper reasoning, while Llama 3.1 405B offers better value for routine operations.
Output costs matter too. GPT-5.4 Pro charges $180.00/1M 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-5.4 Pro 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-5.4 Pro when:
- • You need a larger context window (1,050,000 tokens)
- • You need more capabilities (vision)
- • You need longer outputs (up to 131,072 tokens)
- • You're already using OpenAI's API ecosystem
Choose Llama 3.1 405B when:
- • Budget is a primary concern
- • You're already using Meta (via Together AI)'s API ecosystem
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
GPT-5.4 Pro (OpenAI)
Llama 3.1 405B (Meta (via Together AI))
Start using GPT-5.4 Pro today
Sign Up for OpenAI →Start using Llama 3.1 405B today
Sign Up for Meta (via Together AI) →