GPT-OSS 120B (Groq) vs Kimi K2.5 (Together) — LLM API Cost Comparison
Compare GPT-OSS 120B (Groq) (Groq) vs Kimi K2.5 (Together) (Together AI) on cost per million tokens, context window, and monthly spend.
Prices verified 2026-05-20 · Pricing may change — use the calculator for current estimates
- Input
- $0.15/1M tokens
- Output
- $0.6/1M tokens
- Context
- 128K tokens
- Released
- 2025-12
OpenAI open-source model on Groq; 500 tokens/sec
- Input
- $0.5/1M tokens
- Output
- $2.8/1M tokens
- Context
- 128K tokens
- Released
- 2026-04
Latest Moonshot AI model; strong code & reasoning
Monthly Cost by Usage Tier (70% input / 30% output ratio)
| Usage | GPT-OSS 120B (Groq) | Kimi K2.5 (Together) | Cheaper by |
|---|---|---|---|
| Light (1M tokens) | $0.285 | $1.19 | GPT-OSS 120B (Groq) (76%) |
| Moderate (10M tokens) | $2.85 | $11.90 | GPT-OSS 120B (Groq) (76%) |
| Heavy (100M tokens) | $28.50 | $119 | GPT-OSS 120B (Groq) (76%) |
| Very Heavy (1B tokens) | $285 | $1,190 | GPT-OSS 120B (Groq) (76%) |
Frequently Asked Questions
Which is cheaper — GPT-OSS 120B (Groq) or Kimi K2.5 (Together)?
For input tokens, GPT-OSS 120B (Groq) is cheaper at $0.15/1M tokens — 3.3× less than $0.5/1M. For output tokens, GPT-OSS 120B (Groq) wins at $0.6/1M vs $2.8/1M. At heavy workloads (100M tokens/month), the cost difference can be significant.
What is the context window difference between GPT-OSS 120B (Groq) and Kimi K2.5 (Together)?
GPT-OSS 120B (Groq) supports 128,000 tokens per request; Kimi K2.5 (Together) supports 128,000 tokens. GPT-OSS 120B (Groq) wins on context length, making it better for long documents, large codebases, or extended conversations without chunking.
When should I choose GPT-OSS 120B (Groq) over Kimi K2.5 (Together)?
Choose GPT-OSS 120B (Groq) (Groq) if you prefer Groq's ecosystem, tooling, or reliability track record. OpenAI open-source model on Groq; 500 tokens/sec. Choose Kimi K2.5 (Together) (Together AI) if Latest Moonshot AI model; strong code & reasoning. the price/performance fits your workload better. Use this calculator to find the break-even point for your exact token volume.
How much does 1 billion tokens cost on GPT-OSS 120B (Groq) vs Kimi K2.5 (Together)?
At 700M input + 300M output tokens (1B total): GPT-OSS 120B (Groq) costs $285; Kimi K2.5 (Together) costs $1190. The difference is $905/billion tokens at this 70/30 input/output ratio.