GPT-OSS 120B (Groq) vs Kimi K2.5 (OpenRouter): API Cost Comparison
Compare the API pricing, context windows, features, and real-world cost projections for GPT-OSS 120B (Groq) (Groq) and Kimi K2.5 (OpenRouter) (OpenRouter). Use the interactive calculator below to compute your exact monthly cost based on your token usage and request volume.
Prices verified Mar 10, 2026
Interactive Cost Calculator
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Showing costs for 2 models. Cheapest: GPT-OSS 120B (Groq) at $4.50/month.
| Alert | |||||||
|---|---|---|---|---|---|---|---|
BestGPT-OSS 120B (Groq) | Groq | $4.50 | $0.000450 | $1.50 | $3.00 | 71.0% | Alerts coming soon |
Kimi K2.5 (OpenRouter) | OpenRouter | $15.50 | $0.001550 | $4.50 | $11.00 | — | Alerts coming soon |
Monthly Cost Comparison
Price Comparison at a Glance
All prices are in USD per 1 million tokens ($/M tokens). Lower is cheaper.
| Pricing Type | GPT-OSS 120B (Groq) | Kimi K2.5 (OpenRouter) | Cheaper |
|---|---|---|---|
| Input (standard) | $0.15/M | $0.45/M | GPT-OSS 120B (Groq) |
| Output | $0.60/M | $2.20/M | GPT-OSS 120B (Groq) |
Prices last verified: 2026-03-06 – 2026-03-10
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-OSS 120B (Groq)Monthly | Kimi K2.5 (OpenRouter)Monthly | GPT-OSS 120B (Groq)Per request | Kimi K2.5 (OpenRouter)Per request |
|---|---|---|---|---|
| 1K requests/mo | $0.45 | $1.55 | $0.000450 | $0.001550 |
| 10K requests/mo | $4.50 | $15.50 | $0.000450 | $0.001550 |
| 100K requests/mo | $45.00 | $155.00 | $0.000450 | $0.001550 |
| 1M requests/mo | $450.00 | $1,550.00 | $0.000450 | $0.001550 |
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-OSS 120B (Groq)
by Groq
- General chatbot
- Code generation
Input / 1M tokens
$0.15/M
Output / 1M tokens
$0.60/M
Context window
131,072
Tier
mid
When to Choose Kimi K2.5 (OpenRouter)
by OpenRouter
- Document summarization
- General chatbot
- RAG / Semantic search
Input / 1M tokens
$0.45/M
Output / 1M tokens
$2.20/M
Context window
262,144
Tier
mid
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-OSS 120B (Groq) | Kimi K2.5 (OpenRouter) |
|---|---|---|
| Context window | 131,072 tokens | 262,144 tokens |
| Max output tokens | 32,768 tokens | 65,535 tokens |
| Performance tier | Mid | Mid |
| Vision / image input | No | No |
| Function calling | Yes | Yes |
| JSON mode | Yes | Yes |
| Prompt caching | No | No |
| Batch API (50% discount) | No | No |
| Extended reasoning | No | No |
| Fine-tuning | No | No |
| Rate limit (req/min) | 30 | Not published |
GPT-OSS 120B (Groq) notes
Open-source GPT model with Groq's ultra-fast inference.
Kimi K2.5 (OpenRouter) notes
OpenRouter offers 200+ models — showing top 15 unique models not available from other listed providers. Prices include OpenRouter markup.
Frequently Asked Questions
Is GPT-OSS 120B (Groq) cheaper than Kimi K2.5 (OpenRouter)?
At standard usage (1,000 input tokens, 500 output tokens, 100,000 requests/month), GPT-OSS 120B (Groq) costs $45.00/month versus $155.00/month for Kimi K2.5 (OpenRouter) — a 71% 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-OSS 120B (Groq) or Kimi K2.5 (OpenRouter)?
Kimi K2.5 (OpenRouter) has a larger context window at 262,144 tokens, compared to 131,072 tokens for GPT-OSS 120B (Groq). A larger context window is important for processing long documents, multi-turn conversations, or large codebases without truncation.
Do GPT-OSS 120B (Groq) and Kimi K2.5 (OpenRouter) support the Batch API?
Neither GPT-OSS 120B (Groq) nor Kimi K2.5 (OpenRouter) currently supports a batch API with discounted pricing. For batch-eligible alternatives, consider models from OpenAI, Anthropic, or Google that include batch API support.
Which model offers better prompt caching?
Neither GPT-OSS 120B (Groq) nor Kimi K2.5 (OpenRouter) currently supports prompt caching. For prompt-caching capable alternatives, consider Claude models from Anthropic or GPT-4o from OpenAI.
What are the best use cases for GPT-OSS 120B (Groq) vs Kimi K2.5 (OpenRouter)?
Both models are well-suited for General chatbot. GPT-OSS 120B (Groq) is particularly strong for Code generation. Kimi K2.5 (OpenRouter) is favored for Document summarization, RAG / Semantic search. 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-OSS 120B (Groq) vs Kimi K2.5 (OpenRouter)?
At 1,000 input tokens and 500 output tokens per request — a typical conversational workload — GPT-OSS 120B (Groq) costs $0.000450 per request and Kimi K2.5 (OpenRouter) costs $0.001550 per request. At 100,000 requests/month, that translates to $45.00 and $155.00 respectively. Use the interactive calculator to adjust these parameters for your actual workload.
GPT-OSS 120B (Groq) vs Kimi K2.5 (OpenRouter): Summary
When comparing GPT-OSS 120B (Groq) and Kimi K2.5 (OpenRouter) for API cost, the right choice depends on your workload's token profile, required features, and tolerance for latency. GPT-OSS 120B (Groq) offers lower total cost at standard usage volumes (1,000 input + 500 output tokens per request at 100,000 requests/month) at $45.00/month, compared to $155.00/month for Kimi K2.5 (OpenRouter).
Both models are priced in USD per million tokens, the standard unit across all major AI API providers. GPT-OSS 120B (Groq) charges $0.15/M for input tokens and $0.60/M for output tokens. Kimi K2.5 (OpenRouter) charges $0.45/M input and $2.20/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.
Context window capacity differs between the two: Kimi K2.5 (OpenRouter) supports up to 262,144 tokens in a single request, versus 131,072 tokens for GPT-OSS 120B (Groq). 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
See cost recommendations for workloads where GPT-OSS 120B (Groq) or Kimi K2.5 (OpenRouter) is recommended.