Compare / Kimi K3 vs o3
Kimi K3 vs o3
Which is cheaper, which is more capable, and which does better at each kind of work, from 14 results on 3 sources that measured both models.
Kimi K3 or o3? The short answer
- o3 is cheaper: $3.50 against $6.00 per million tokens, 42% less.
- Kimi K3 scores higher on the Artificial Analysis Intelligence Index: 43.6 against 20.2.
- o3 writes faster: 126 tokens a second against 45.
- On our business benchmarks, Kimi K3 ranks higher for reasoning and knowledge, writing and sticking to the facts.
- On our business benchmarks, o3 ranks higher for agents and tool use.
At a glance
| Kimi K3 | o3 | |
|---|---|---|
| Price per million tokens | $3.00 in · $15.00 out | $2.00 in · $8.00 out |
| Blended (3 in : 1 out) | $6.00 | $3.50 |
| Cheapest host, blended | $3.71 (Relace, FP4) | – |
| Intelligence Index | 43.6 | 20.2 |
| Spring Prompt overall | 49 | – |
| Output speed, tokens a second | 45 | 126 |
| Context window | 1,048,576 tokens | 200,000 tokens |
| Weights | Open | Closed |
| Developer based in | China | the US |
Prices are the developer's list price where we have read it, otherwise the typical host on OpenRouter; see every model's price. Intelligence and speed from Artificial Analysis.
Which is better for what
Each model's rank among models available today, for each kind of work, from our own benchmarks and licensed sources. The better rank is in green.
| Use case | Kimi K3 | o3 |
|---|---|---|
| Product listingsTurning a sparse product feed and photos into listings that can go live | 12 of 19 | not measured |
| Decks from an analysisTurning a finished analysis into a deck you could present as it is | 8 of 18 | not measured |
| Marketing planningPlanning a year of ad spend without overspending | 8 of 18 | not measured |
| Agents and tool useMulti-step tasks with tools: support desks, coding agents, function calls | 32 of 161 | 13 of 161 |
| Professional workReal tasks from banking, consulting and law, business documents and freelance projects | 24 of 51 | not measured |
| Reasoning and knowledgeHard questions across science, maths and general knowledge | 15 of 195 | 95 of 195 |
| WritingWhat people prefer in blind comparisons, and judged writing quality | 11 of 187 | 49 of 187 |
| Sticking to the factsSummarising without inventing things, and factual answers | 31 of 153 | 91 of 153 |
| Speed under pressureGood decisions against a real clock (fast chess) | 18 of 21 | not measured |
Every shared result
| Benchmark | Metric | Kimi K3 | o3 |
|---|---|---|---|
| Arena (formerly LMArena)reported | OverallArena rating | 1,472 | 1,405 |
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,489 | 1,426 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,458 | 1,383 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,533 | 1,449 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,486 | 1,403 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,488 | 1,432 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,475 | 1,396 |
| Artificial Analysisreported | Artificial Analysis Intelligence Indexindex score | 43.6 | 20.2 |
| Artificial Analysisreported | GPQA Diamond% of questions | 93.5% | 82.7% |
| Artificial Analysisreported | Humanity's Last Exam% of questions | 46.9% | 20.1% |
| Artificial Analysisreported | Long-context reasoning (AA-LCR)% of questions | 88.7% | 74.7% |
| Artificial Analysisreported | Output speedtokens per second | 45.1 | 126 |
| Artificial Analysisreported | Time to first answer tokenseconds | 47.0 | 3.96 |
| SimpleQA Verified (Epoch AI)reported | Correct answers% of questions | 50.6% | 49.4% |
Bold green marks the better value on that metric. Where a source reports ranges that overlap, the difference may not be meaningful; see the benchmark page for ranges.
Quick answers
Is Kimi K3 better than o3?
It depends on the task. Among models available today, on our benchmarks and licensed sources, Kimi K3 ranks higher for reasoning and knowledge, writing and sticking to the facts; o3 ranks higher for agents and tool use.
Which is cheaper, Kimi K3 or o3?
o3 costs $3.50 per million tokens (three input to one output), against $6.00 for Kimi K3.
Which is faster, Kimi K3 or o3?
o3 writes about 126 tokens a second on its usual API, against 45 for Kimi K3 (Artificial Analysis).
Run Kimi K3 and o3 on your own prompt
Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.