GPT-4o vs Llama 3.1 405B (Together AI): API Cost Comparison
Compare the API pricing, context windows, features, and real-world cost projections for GPT-4o (OpenAI) and Llama 3.1 405B (Together AI) (Together AI). Use the interactive calculator below to compute your exact monthly cost based on your token usage and request volume.
Prices verified Mar 6, 2026
Interactive Cost Calculator
Fills in typical token counts for a workload type
Tokens in each prompt sent to the model
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Showing costs for 2 models. Cheapest: Llama 3.1 405B (Together AI) at $52.50/month.
| Alert | |||||||
|---|---|---|---|---|---|---|---|
BestLlama 3.1 405B (Together AI) | Together AI | $52.50 | $0.005250 | $35.00 | $17.50 | 30.0% | Alerts coming soon |
GPT-4o | OpenAI | $75.00 | $0.007500 | $25.00 | $50.00 | — | Alerts coming soon |
Monthly Cost Comparison
Price Comparison at a Glance
All prices are in USD per 1 million tokens ($/M tokens). Lower is cheaper.
| Pricing Type | GPT-4o | Llama 3.1 405B (Together AI) | Cheaper |
|---|---|---|---|
| Input (standard) | $2.50/M | $3.50/M | GPT-4o |
| Output | $10.00/M | $3.50/M | Llama 3.1 405B (Together AI) |
| Cached input | $1.25/M | N/A | — |
| Batch input | $1.25/M | N/A | — |
| Batch output | $5.00/M | N/A | — |
Prices last verified: 2026-03-06
Cost Breakdown by Usage Volume
Estimated monthly costs at different request volumes, assuming 1,000 input tokens and 500 output tokens per request. Adjust in the calculator above for your specific use case.
| Volume | GPT-4oMonthly | Llama 3.1 405B (Together AI)Monthly | GPT-4oPer request | Llama 3.1 405B (Together AI)Per request |
|---|---|---|---|---|
| 1K requests/mo | $7.50 | $5.25 | $0.007500 | $0.005250 |
| 10K requests/mo | $75.00 | $52.50 | $0.007500 | $0.005250 |
| 100K requests/mo | $750.00 | $525.00 | $0.007500 | $0.005250 |
| 1M requests/mo | $7,500.00 | $5,250.00 | $0.007500 | $0.005250 |
Green values indicate the lower-cost option at each volume tier. Cost per request is calculated at 1,000 input + 500 output tokens using standard (non-batch, non-cached) pricing.
Price History
Input price per 1M tokensWhen to Choose GPT-4o
by OpenAI
- General chatbot
- Code generation
- Content & copywriting
Input / 1M tokens
$2.50/M
Output / 1M tokens
$10.00/M
Context window
128,000
Tier
premium
When to Choose Llama 3.1 405B (Together AI)
by Together AI
- Code generation
- Content & copywriting
- Document summarization
Input / 1M tokens
$3.50/M
Output / 1M tokens
$3.50/M
Context window
131,072
Tier
premium
Key Differences Beyond Price
Cost is only one factor in choosing an AI model. Context window size, rate limits, supported features, and latency all affect whether a model fits your use case.
| Capability | GPT-4o | Llama 3.1 405B (Together AI) |
|---|---|---|
| Context window | 128,000 tokens | 131,072 tokens |
| Max output tokens | 16,384 tokens | 4,096 tokens |
| Performance tier | Premium | Premium |
| Vision / image input | Yes | No |
| Function calling | Yes | Yes |
| JSON mode | Yes | Yes |
| Prompt caching | Yes | No |
| Batch API (50% discount) | Yes | No |
| Extended reasoning | No | No |
| Fine-tuning | Yes | No |
| Rate limit (req/min) | 10,000 | Not published |
GPT-4o notes
Snapshot versions available (gpt-4o-2024-11-20). Cached input requires cache_control.
Llama 3.1 405B (Together AI) notes
Largest open-source model available via API. Meta license allows commercial use.
Frequently Asked Questions
Is GPT-4o cheaper than Llama 3.1 405B (Together AI)?
At standard usage (1,000 input tokens, 500 output tokens, 100,000 requests/month), Llama 3.1 405B (Together AI) costs $525.00/month versus $750.00/month for GPT-4o — a 30% saving. Your actual savings will vary based on your token profile; output-heavy workloads amplify differences in output pricing.
Which model has a larger context window, GPT-4o or Llama 3.1 405B (Together AI)?
Llama 3.1 405B (Together AI) has a larger context window at 131,072 tokens, compared to 128,000 tokens for GPT-4o. A larger context window is important for processing long documents, multi-turn conversations, or large codebases without truncation.
Do GPT-4o and Llama 3.1 405B (Together AI) support the Batch API?
GPT-4o supports the Batch API (50% discount for async processing), while Llama 3.1 405B (Together AI) does not. If your workload tolerates up to 24-hour latency, routing to GPT-4o with batch pricing could significantly cut costs versus Llama 3.1 405B (Together AI)'s standard rate.
Which model offers better prompt caching?
GPT-4o supports prompt caching at $1.25/M for cached input, while Llama 3.1 405B (Together AI) does not offer prompt caching. For RAG applications or chatbots with large, repeated context, GPT-4o's caching capability can substantially reduce effective costs.
What are the best use cases for GPT-4o vs Llama 3.1 405B (Together AI)?
Both models are well-suited for Code generation, Content & copywriting. GPT-4o is particularly strong for General chatbot. Llama 3.1 405B (Together AI) is favored for Document summarization. At the same quality level, the lower-cost model is usually preferable; use this page's calculator to compare total monthly spend at your volume.
What is the cost per request for GPT-4o vs Llama 3.1 405B (Together AI)?
At 1,000 input tokens and 500 output tokens per request — a typical conversational workload — GPT-4o costs $0.007500 per request and Llama 3.1 405B (Together AI) costs $0.005250 per request. At 100,000 requests/month, that translates to $750.00 and $525.00 respectively. Use the interactive calculator to adjust these parameters for your actual workload.
GPT-4o vs Llama 3.1 405B (Together AI): Summary
When comparing GPT-4o and Llama 3.1 405B (Together AI) for API cost, the right choice depends on your workload's token profile, required features, and tolerance for latency. Llama 3.1 405B (Together AI) offers lower total cost at standard usage volumes (1,000 input + 500 output tokens per request at 100,000 requests/month) at $525.00/month, compared to $750.00/month for GPT-4o.
Both models are priced in USD per million tokens, the standard unit across all major AI API providers. GPT-4o charges $2.50/M for input tokens and $10.00/M for output tokens. Llama 3.1 405B (Together AI) charges $3.50/M input and $3.50/M output. If your workload is output-heavy (more tokens generated than consumed as input), the model with the lower output price compounds cost savings significantly at scale.
Prompt caching is supported by GPT-4o but not Llama 3.1 405B (Together AI). For workloads with large, repeated system prompts or document context — such as RAG pipelines or multi-turn conversations with a fixed knowledge base — prompt caching can reduce effective input costs by 60–90%, which may change the cost ranking between these two models at your specific usage pattern.
Context window capacity differs between the two: Llama 3.1 405B (Together AI) supports up to 131,072 tokens in a single request, versus 128,000 tokens for GPT-4o. A larger context window is essential for document summarization, large codebase analysis, and multi-document retrieval-augmented generation (RAG) applications.
Use the interactive calculator at the top of this page to enter your actual token usage and monthly request volume for a precise cost comparison tailored to your workload. Adjust for batch API discounts and prompt caching to find the most cost-effective option for your specific deployment.
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Relevant Use Cases
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