Claude Sonnet 4.5
VS
Kimi K2.5
Claude Sonnet 4.5 vs Kimi K2.5: which wins at real work?
22 task areas · same graded test runs · rank comparison only, so 0–100 and Elo collections never mix raw scores.
Kimi K2.5 wins 17 of 22 task areas we tested; Claude Sonnet 4.5 takes 5. Kimi K2.5 costs 7.5× less per token ($2.4 vs $18 per 1M).
Kimi K2.5 costs 7.5× less per token ($2.4 vs $18 per 1M).
Task by task
| Task area | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|---|---|---|---|
| Summarization & Meeting Notes |
#2
/ 110
Excellent
|
#92
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Content & Brand |
#74
/ 124
Usable
|
#33
/ 124
Strong
|
Kimi K2.5 |
| AI Strategy |
#67
/ 126
Strong
|
#28
/ 126
Strong
|
Kimi K2.5 |
| Structured Output |
#80
/ 113
Strong
|
#41
/ 113
Excellent
|
Kimi K2.5 |
| Legal & HR |
#69
/ 110
Strong
|
#31
/ 110
Excellent
|
Kimi K2.5 |
| Chef / Home Cooking |
#80
/ 126
Usable
|
#44
/ 126
Usable
|
Kimi K2.5 |
| Knowledge & Docs |
#28
/ 110
Strong
|
#59
/ 110
Usable
|
Claude Sonnet 4.5 |
| Presentations & Decks |
#43
/ 110
Excellent
|
#12
/ 110
Excellent
|
Kimi K2.5 |
| Training & Education |
#51
/ 110
Excellent
|
#22
/ 110
Excellent
|
Kimi K2.5 |
| RAG, Safety & Grounding |
#39
/ 113
Excellent
|
#12
/ 113
Excellent
|
Kimi K2.5 |
| Coding |
#62
/ 115
Strong
|
#38
/ 115
Strong
|
Kimi K2.5 |
| Creative & Comedy | #66 / 110 | #42 / 110 | Kimi K2.5 |
| Data & Analytics |
#33
/ 110
Excellent
|
#19
/ 110
Excellent
|
Kimi K2.5 |
| Landing Pages |
#30
/ 72
Strong
|
#20
/ 72
Strong
|
Kimi K2.5 |
| Sales |
#10
/ 110
Strong
|
#19
/ 110
Strong
|
Claude Sonnet 4.5 |
| Translation & Localization |
#25
/ 110
Excellent
|
#34
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Executive Assistant |
#31
/ 112
Strong
|
#23
/ 112
Strong
|
Kimi K2.5 |
| Research & Competitive Analysis |
#39
/ 110
Strong
|
#31
/ 110
Strong
|
Kimi K2.5 |
| Customer Support |
#43
/ 113
Strong
|
#50
/ 113
Strong
|
Claude Sonnet 4.5 |
| Investor & Pitch |
#42
/ 66
Usable
|
#37
/ 66
Usable
|
Kimi K2.5 |
| Product & Project Management |
#71
/ 110
Strong
|
#66
/ 110
Strong
|
Kimi K2.5 |
| Frontend & Landing Pages |
#29
/ 109
Needs editing
|
#26
/ 109
Needs editing
|
Kimi K2.5 |
Rank = position among every model config we tested in that task area (lower is better). Sorted by biggest gap first.
Frequently asked
Is Claude Sonnet 4.5 better than Kimi K2.5?
Across 22 task areas we benchmarked, Kimi K2.5 ranks higher in 17 and Claude Sonnet 4.5 in 5.
Which is cheaper, Claude Sonnet 4.5 or Kimi K2.5?
Kimi K2.5 costs 7.5× less per token ($2.4 vs $18 per 1M).
What is Claude Sonnet 4.5 better at?
Claude Sonnet 4.5 out-ranks Kimi K2.5 at Summarization & Meeting Notes, Knowledge & Docs, Sales.
What is Kimi K2.5 better at?
Kimi K2.5 out-ranks Claude Sonnet 4.5 at Content & Brand, AI Strategy, Structured Output.
More comparisons
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Prompt × model results
12 test cases · 3 evals