GPT-5 Mini vs Kimi K2.5
Complete pricing and performance comparison between OpenAI's GPT-5 Mini and Moonshot's Kimi K2.5.
Quick Verdict
Cheaper
GPT-5 Mini
2.4x cheaper input, 1.5x cheaper output
Larger Context
GPT-5 Mini
400K vs 128K
Higher Quality
Kimi K2.5
Score: 47 vs 41
Faster
GPT-5 Mini
82 vs 46 tok/s
Pricing Comparison
| Spec | GPT-5 Mini | Kimi K2.5 | Difference |
|---|---|---|---|
| Provider | OpenAI | Moonshot | |
| Input / 1M tokens | $0.25 | $0.6 | GPT-5 Mini is 58% more expensive |
| Output / 1M tokens | $2 | $3 | GPT-5 Mini is 33% more expensive |
| Context Window | 400K | 128K | 3x difference |
| Max Output | 16K | 33K | |
| Tokenizer | o200k_base | cl100k_base |
Performance Benchmarks
| Metric | GPT-5 Mini | Kimi K2.5 | Winner |
|---|---|---|---|
| Quality Index | 41 | 47 | Kimi K2.5 |
| Output Speed | 82 tok/s | 46 tok/s | GPT-5 Mini |
| Time to First Token | 99.18s | 1.05s | Kimi K2.5 |
| Value (Quality/$) | 164.8 | 78.0 | Higher = better value |
Benchmark data from Artificial Analysis. Quality Index is a composite score across reasoning, coding, and knowledge tasks.
Cost at Scale
Estimated cost at different usage levels (3:1 input-to-output token ratio, typical for chat).
| Usage | GPT-5 Mini | Kimi K2.5 | Savings |
|---|---|---|---|
Single request 1K in / 300 out | $0.0008 | $0.0015 | Same |
10 requests 10K in / 3K out | $0.0085 | $0.015 | GPT-5 Mini saves $0.0065 |
100 requests 100K in / 30K out | $0.085 | $0.150 | GPT-5 Mini saves $0.065 |
1,000 requests 1M in / 300K out | $0.850 | $1.50 | GPT-5 Mini saves $0.650 |
10,000 requests 10M in / 3M out | $8.50 | $15.00 | GPT-5 Mini saves $6.50 |
1M requests/mo 1B in / 300M out | $850.00 | $1500.00 | GPT-5 Mini saves $650.00 |
Pros & Cons
GPT-5 Mini Strengths
- +Cheaper input tokens
- +Cheaper output tokens
- +Larger context window (400K vs 128K)
- +Faster output (82 vs 46 tok/s)
Kimi K2.5 Strengths
- +Higher max output tokens
- +Higher quality score (47 vs 41)
- +Lower latency (faster first token)
When to Use Each Model
Choose GPT-5 Mini for
- →Budget-conscious projects where cost is the primary factor
- →Long documents, large codebases, or multi-turn conversations
- →Real-time applications, chat, or autocomplete
Choose Kimi K2.5 for
- →Generating long-form content or detailed code
- →Tasks requiring maximum accuracy and reasoning
Frequently Asked Questions
Which is cheaper, GPT-5 Mini or Kimi K2.5?
For input tokens, GPT-5 Mini is 2.4x cheaper at $0.25/1M tokens. For output tokens, GPT-5 Mini is 1.5x cheaper at $2/1M tokens. At typical usage (1M input + 300K output), GPT-5 Mini costs $0.850 vs Kimi K2.5 at $1.50.
What's the context window difference?
GPT-5 Mini supports 400K context (400,000 tokens), while Kimi K2.5 supports 128K (128,000 tokens). GPT-5 Mini can handle 3x more context in a single request.
Which model has better benchmarks?
Quality Index: GPT-5 Mini scores 41 vs Kimi K2.5 at 47. Speed: GPT-5 Mini generates 82 tok/s vs Kimi K2.5 at 46 tok/s. Time to first token: GPT-5 Mini at 99.18s vs Kimi K2.5 at 1.05s.
When should I choose GPT-5 Mini over Kimi K2.5?
Choose GPT-5 Mini when you need: Cheaper input tokens, Cheaper output tokens, Larger context window (400K vs 128K), Faster output (82 vs 46 tok/s). Choose Kimi K2.5 when you need: Higher max output tokens, Higher quality score (47 vs 41), Lower latency (faster first token).
How much would 10,000 API requests cost?
At 1K input + 300 output tokens per request (typical chat): GPT-5 Mini = $8.50, Kimi K2.5 = $15.00. At 10K input + 1K output per request (longer conversations): GPT-5 Mini = $45.00, Kimi K2.5 = $90.00.