GPT-4o vs Kimi K2.5
Complete pricing and performance comparison between OpenAI's GPT-4o and Moonshot's Kimi K2.5.
Quick Verdict
Cheaper
Kimi K2.5
4.2x cheaper input, 3.3x cheaper output
Larger Context
GPT-4o
128K vs 128K
Higher Quality
Kimi K2.5
Score: 47 vs 17
Faster
GPT-4o
135 vs 46 tok/s
Pricing Comparison
| Spec | GPT-4o | Kimi K2.5 | Difference |
|---|---|---|---|
| Provider | OpenAI | Moonshot | |
| Input / 1M tokens | $2.5 | $0.6 | Kimi K2.5 is 76% more expensive |
| Output / 1M tokens | $10 | $3 | Kimi K2.5 is 70% more expensive |
| Context Window | 128K | 128K | Same |
| Max Output | 16K | 33K | |
| Tokenizer | o200k_base | cl100k_base |
Performance Benchmarks
| Metric | GPT-4o | Kimi K2.5 | Winner |
|---|---|---|---|
| Quality Index | 17 | 47 | Kimi K2.5 |
| Output Speed | 135 tok/s | 46 tok/s | GPT-4o |
| Time to First Token | 0.53s | 1.05s | GPT-4o |
| Value (Quality/$) | 6.9 | 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-4o | Kimi K2.5 | Savings |
|---|---|---|---|
Single request 1K in / 300 out | $0.0055 | $0.0015 | Kimi K2.5 saves $0.0040 |
10 requests 10K in / 3K out | $0.055 | $0.015 | Kimi K2.5 saves $0.040 |
100 requests 100K in / 30K out | $0.550 | $0.150 | Kimi K2.5 saves $0.400 |
1,000 requests 1M in / 300K out | $5.50 | $1.50 | Kimi K2.5 saves $4.00 |
10,000 requests 10M in / 3M out | $55.00 | $15.00 | Kimi K2.5 saves $40.00 |
1M requests/mo 1B in / 300M out | $5500.00 | $1500.00 | Kimi K2.5 saves $4000.00 |
Pros & Cons
GPT-4o Strengths
- +Faster output (135 vs 46 tok/s)
- +Lower latency (faster first token)
Kimi K2.5 Strengths
- +Cheaper input tokens
- +Cheaper output tokens
- +Higher max output tokens
- +Higher quality score (47 vs 17)
When to Use Each Model
Choose GPT-4o for
- →Real-time applications, chat, or autocomplete
Choose Kimi K2.5 for
- →Budget-conscious projects where cost is the primary factor
- →Generating long-form content or detailed code
- →Tasks requiring maximum accuracy and reasoning
Frequently Asked Questions
Which is cheaper, GPT-4o or Kimi K2.5?
For input tokens, Kimi K2.5 is 4.2x cheaper at $0.6/1M tokens. For output tokens, Kimi K2.5 is 3.3x cheaper at $3/1M tokens. At typical usage (1M input + 300K output), GPT-4o costs $5.50 vs Kimi K2.5 at $1.50.
What's the context window difference?
GPT-4o supports 128K context (128,000 tokens), while Kimi K2.5 supports 128K (128,000 tokens). Kimi K2.5 can handle 1x more context in a single request.
Which model has better benchmarks?
Quality Index: GPT-4o scores 17 vs Kimi K2.5 at 47. Speed: GPT-4o generates 135 tok/s vs Kimi K2.5 at 46 tok/s. Time to first token: GPT-4o at 0.53s vs Kimi K2.5 at 1.05s.
When should I choose GPT-4o over Kimi K2.5?
Choose GPT-4o when you need: Faster output (135 vs 46 tok/s), Lower latency (faster first token). Choose Kimi K2.5 when you need: Cheaper input tokens, Cheaper output tokens, Higher max output tokens, Higher quality score (47 vs 17).
How much would 10,000 API requests cost?
At 1K input + 300 output tokens per request (typical chat): GPT-4o = $55.00, Kimi K2.5 = $15.00. At 10K input + 1K output per request (longer conversations): GPT-4o = $350.00, Kimi K2.5 = $90.00.