GPT-5.4 Mini vs Kimi K2.5
Complete pricing and performance comparison between OpenAI's GPT-5.4 Mini and Moonshot's Kimi K2.5.
Quick Verdict
Cheaper
Kimi K2.5
1.3x cheaper input, 1.5x cheaper output
Larger Context
GPT-5.4 Mini
400K vs 128K
Pricing Comparison
| Spec | GPT-5.4 Mini | Kimi K2.5 | Difference |
|---|---|---|---|
| Provider | OpenAI | Moonshot | |
| Input / 1M tokens | $0.75 | $0.6 | Kimi K2.5 is 20% more expensive |
| Output / 1M tokens | $4.5 | $3 | Kimi K2.5 is 33% more expensive |
| Context Window | 400K | 128K | 3x difference |
| Max Output | 128K | 33K | |
| Tokenizer | o200k_base | cl100k_base |
Performance Benchmarks
| Metric | GPT-5.4 Mini | Kimi K2.5 | Winner |
|---|---|---|---|
| Quality Index | -- | 47 | N/A |
| Output Speed | -- | 34 tok/s | N/A |
| Value (Quality/$) | -- | 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-5.4 Mini | Kimi K2.5 | Savings |
|---|---|---|---|
Single request 1K in / 300 out | $0.0021 | $0.0015 | Same |
10 requests 10K in / 3K out | $0.021 | $0.015 | Kimi K2.5 saves $0.0060 |
100 requests 100K in / 30K out | $0.210 | $0.150 | Kimi K2.5 saves $0.060 |
1,000 requests 1M in / 300K out | $2.10 | $1.50 | Kimi K2.5 saves $0.600 |
10,000 requests 10M in / 3M out | $21.00 | $15.00 | Kimi K2.5 saves $6.00 |
1M requests/mo 1B in / 300M out | $2100.00 | $1500.00 | Kimi K2.5 saves $600.00 |
Pros & Cons
GPT-5.4 Mini Strengths
- +Larger context window (400K vs 128K)
- +Higher max output tokens
Kimi K2.5 Strengths
- +Cheaper input tokens
- +Cheaper output tokens
When to Use Each Model
Choose GPT-5.4 Mini for
- →Long documents, large codebases, or multi-turn conversations
- →Generating long-form content or detailed code
Choose Kimi K2.5 for
- →Budget-conscious projects where cost is the primary factor
Frequently Asked Questions
Which is cheaper, GPT-5.4 Mini or Kimi K2.5?
For input tokens, Kimi K2.5 is 1.3x cheaper at $0.6/1M tokens. For output tokens, Kimi K2.5 is 1.5x cheaper at $3/1M tokens. At typical usage (1M input + 300K output), GPT-5.4 Mini costs $2.10 vs Kimi K2.5 at $1.50.
What's the context window difference?
GPT-5.4 Mini supports 400K context (400,000 tokens), while Kimi K2.5 supports 128K (128,000 tokens). GPT-5.4 Mini can handle 3x more context in a single request.
Which model has better benchmarks?
When should I choose GPT-5.4 Mini over Kimi K2.5?
Choose GPT-5.4 Mini when you need: Larger context window (400K vs 128K), Higher max output tokens. Choose Kimi K2.5 when you need: Cheaper input tokens, Cheaper output tokens.
How much would 10,000 API requests cost?
At 1K input + 300 output tokens per request (typical chat): GPT-5.4 Mini = $21.00, Kimi K2.5 = $15.00. At 10K input + 1K output per request (longer conversations): GPT-5.4 Mini = $120.00, Kimi K2.5 = $90.00.