Grok 4-20 vs Kimi K2.5
Complete pricing and performance comparison between xAI's Grok 4-20 and Moonshot's Kimi K2.5.
Quick Verdict
Cheaper
Kimi K2.5
3.3x cheaper input, 2.0x cheaper output
Larger Context
Grok 4-20
131K vs 128K
Higher Quality
Grok 4-20
Score: 49 vs 47
Faster
Grok 4-20
101 vs 34 tok/s
Pricing Comparison
| Spec | Grok 4-20 | Kimi K2.5 | Difference |
|---|---|---|---|
| Provider | xAI | Moonshot | |
| Input / 1M tokens | $2 | $0.6 | Kimi K2.5 is 70% more expensive |
| Output / 1M tokens | $6 | $3 | Kimi K2.5 is 50% more expensive |
| Context Window | 131K | 128K | 1x difference |
| Max Output | 16K | 33K |
Performance Benchmarks
| Metric | Grok 4-20 | Kimi K2.5 | Winner |
|---|---|---|---|
| Quality Index | 49 | 47 | Grok 4-20 |
| Output Speed | 101 tok/s | 34 tok/s | Grok 4-20 |
| Time to First Token | 20.69s | 1.35s | Kimi K2.5 |
| Value (Quality/$) | 24.3 | 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 | Grok 4-20 | Kimi K2.5 | Savings |
|---|---|---|---|
Single request 1K in / 300 out | $0.0038 | $0.0015 | Kimi K2.5 saves $0.0023 |
10 requests 10K in / 3K out | $0.038 | $0.015 | Kimi K2.5 saves $0.023 |
100 requests 100K in / 30K out | $0.380 | $0.150 | Kimi K2.5 saves $0.230 |
1,000 requests 1M in / 300K out | $3.80 | $1.50 | Kimi K2.5 saves $2.30 |
10,000 requests 10M in / 3M out | $38.00 | $15.00 | Kimi K2.5 saves $23.00 |
1M requests/mo 1B in / 300M out | $3800.00 | $1500.00 | Kimi K2.5 saves $2300.00 |
Pros & Cons
Grok 4-20 Strengths
- +Larger context window (131K vs 128K)
- +Faster output (101 vs 34 tok/s)
- +Higher quality score (49 vs 47)
Kimi K2.5 Strengths
- +Cheaper input tokens
- +Cheaper output tokens
- +Higher max output tokens
- +Lower latency (faster first token)
When to Use Each Model
Choose Grok 4-20 for
- →Long documents, large codebases, or multi-turn conversations
- →Tasks requiring maximum accuracy and reasoning
- →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
Frequently Asked Questions
Which is cheaper, Grok 4-20 or Kimi K2.5?
For input tokens, Kimi K2.5 is 3.3x cheaper at $0.6/1M tokens. For output tokens, Kimi K2.5 is 2.0x cheaper at $3/1M tokens. At typical usage (1M input + 300K output), Grok 4-20 costs $3.80 vs Kimi K2.5 at $1.50.
What's the context window difference?
Grok 4-20 supports 131K context (131,072 tokens), while Kimi K2.5 supports 128K (128,000 tokens). Grok 4-20 can handle 1x more context in a single request.
Which model has better benchmarks?
Quality Index: Grok 4-20 scores 49 vs Kimi K2.5 at 47. Speed: Grok 4-20 generates 101 tok/s vs Kimi K2.5 at 34 tok/s. Time to first token: Grok 4-20 at 20.69s vs Kimi K2.5 at 1.35s.
When should I choose Grok 4-20 over Kimi K2.5?
Choose Grok 4-20 when you need: Larger context window (131K vs 128K), Faster output (101 vs 34 tok/s), Higher quality score (49 vs 47). Choose Kimi K2.5 when you need: Cheaper input tokens, Cheaper output tokens, Higher max output tokens, Lower latency (faster first token).
How much would 10,000 API requests cost?
At 1K input + 300 output tokens per request (typical chat): Grok 4-20 = $38.00, Kimi K2.5 = $15.00. At 10K input + 1K output per request (longer conversations): Grok 4-20 = $260.00, Kimi K2.5 = $90.00.