Quick Verdict
| Need | Better first pick | Why |
|---|---|---|
| Open-model breadth | Together AI | One API for many open and open-adjacent model families |
| Proprietary GPT quality | OpenAI | Better default for GPT-specific workflows and premium reasoning |
| Cheap hosted text | Together GPT-OSS or MiniMax | Low per-token rates for bulk workloads |
| Multimodal and ecosystem depth | OpenAI | Stronger platform coverage and integrations |
| Provider diversification | Together AI | Easier to avoid betting everything on one closed model stack |
Use the chart and calculator above to compare the 2-4 routes that matter for your traffic. If open-model cost is the main question, also compare DeepSeek vs OpenAI pricing.
Pricing Table
| Provider | Model | Input | Cached input | Output | Best fit |
|---|---|---|---|---|---|
| Together AI | GPT-OSS 20B | $0.05 | n/a | $0.20 | Low-cost open-model chat and routing |
| Together AI | GPT-OSS 120B | $0.15 | n/a | $0.60 | Larger open model at low cost |
| Together AI | MiniMax M3 | $0.30 | $0.06 | $1.20 | General production text with cache support |
| Together AI | Kimi K2.7 Code | $0.95 | $0.19 | $4.00 | Coding-focused open-model route |
| Together AI | DeepSeek V4 Pro | $1.74 | n/a | $3.48 | Stronger DeepSeek route through a hosted platform |
| OpenAI | GPT-5.6 Luna | $1.00 | $0.10 | $6.00 | Lower-cost current GPT-5.6 route |
| OpenAI | GPT-5.6 Sol | $5.00 | $0.50 | $30.00 | Premium OpenAI flagship route |
Together AI is not trying to be ChatGPT. It is a hosted open-model platform. That makes it useful when your pricing problem is flexibility, model variety, or a cheaper route for text tasks that do not need GPT-5.6 Sol.
Where Together Wins
Together is compelling for open-model evaluation, provider diversification, fine-tuning paths, and lower-cost hosted text. It gives teams a way to test GPT-OSS, MiniMax, Kimi, DeepSeek, Qwen, Llama, and related families without building separate integrations for every provider.
Where OpenAI Wins
OpenAI wins when you need the proprietary GPT product surface, mature multimodal tooling, broad ecosystem support, and premium reasoning ceiling. GPT-5.6 Luna also makes the OpenAI side less expensive than older GPT-only comparisons.
Routing Table
| Workload | First route | Escalation route |
|---|---|---|
| Simple text routing | Together GPT-OSS 20B | GPT-5.6 Luna |
| General support draft | Together MiniMax M3 | GPT-5.6 Luna |
| Coding task | Together Kimi K2.7 Code | GPT-5.6 Sol |
| Open-model eval | Together model basket | OpenAI baseline |
| Premium GPT workflow | GPT-5.6 Luna | GPT-5.6 Sol |
FAQ
Is Together AI cheaper than OpenAI?
Often for open-model text routes, yes. GPT-5.6 Luna narrows the gap for OpenAI-first teams, but GPT-5.6 Sol remains far more expensive than most Together routes.
Is Together AI a replacement for OpenAI?
Not for every workload. It is best as an open-model host, evaluation layer, or cost-control route alongside OpenAI.
Which Together model should I test first?
Start with GPT-OSS 20B for cheap text, MiniMax M3 for general production text, and Kimi K2.7 Code for coding-focused experiments.
When should I choose OpenAI anyway?
Choose OpenAI when GPT-specific quality, multimodal features, mature tooling, or enterprise familiarity is worth more than the token savings.
Bottom Line
Together AI is the stronger first test for open-model breadth and cheap hosted text. OpenAI is the safer default for proprietary GPT workflows and premium platform coverage. Use Together to lower routine costs and keep OpenAI for workflows that need GPT quality or ecosystem depth.