Model comparison
Kimi K2 vs o3
Head-to-head evidence from 14 shared benchmark results across 7 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Kimi K2 #189 (Supported); o3 #131 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Kimi K2 and o3 share 14 comparable benchmark results. 1 of 8 categories are comparable. 0 results are unique to Kimi K2; 2 to o3.
Updated July 20, 2026- Shared results
- 14
- Kimi K2 only
- 0
- o3 only
- 2
- Comparable categories
- 1 / 8
Pick o3 if you want the stronger benchmark profile. Kimi K2 only becomes the better choice if mathematics is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 14 shared benchmark results across 7 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
o3 is clearly ahead on the BenchAlign aggregate, 47.89 to 27.19. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
o3 is also the more expensive model on tokens at $2.00 input / $8.00 output per 1M tokens, versus $0.60 input / $2.50 output per 1M tokens for Kimi K2. That is roughly 3.2x on output cost alone. o3 is the reasoning model in the pair, while Kimi K2 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. o3 gives you the larger context window at 200K, compared with 128K for Kimi K2.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Kimi K2 | Δ | o3 |
|---|---|---|---|
| Math | Kimi K216.1 | Margin← 1.6 | o314.5 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
FrontierMath v2 (Tiers 1-3)
MathA 21.404%B 18.685%Winner: Kimi K2Δ 2.7FrontierMath v2 (Tiers 1-3): Kimi K2 scored 21.404%; o3 scored 18.685%. Kimi K2 wins this benchmark. - Source ↗
FrontierMath v2 (Tier 4)
MathA 0.000%B 2.083%Winner: o3Δ 2.1FrontierMath v2 (Tier 4): Kimi K2 scored 0.000%; o3 scored 2.083%. o3 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Kimi K2 | o3 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Kimi K2$0.6 input / $2.5 output | o3$2 input / $8 output | Kimi K2 has the lower combined listed price. |
| Generation speedtokens per second | Kimi K243 tok/s | o3118 tok/s | o3 has the higher measured throughput. |
| First-answer latencyseconds to first token | Kimi K21.51 s | o35.38 s | Kimi K2 reaches the first token sooner. |
| Context windowmaximum listed tokens | Kimi K2128K | o3200K | o3 lists the larger context window. |
Benchmark Deep Dive
Agentic1 benchmarks
| Benchmark | Kimi K2 | o3 | Result |
|---|---|---|---|
| τ²-bench resultsSource | 61.1% | 80.7% | o3 leads |
Coding1 benchmarks
| Benchmark | Kimi K2 | o3 | Result |
|---|---|---|---|
| AA-SciCodeSource | 34.5% | 41.0% | o3 leads |
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | Kimi K2 | o3 | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 19.4% | 30.4% | o3 leads |
| AA-GPQA DiamondSource | 76.6% | 82.7% | o3 leads |
| AA-HLESource | 7.0% | 20.0% | o3 leads |
| AA-Omniscience IndexSource | -27.5% | -15.3% | o3 leads |
| AA-Omniscience AccuracySource | 26.8% | 38.4% | o3 leads |
| AA-Omniscience Hallucination RateSource | 74.2% | 87.1% | Kimi K2 leads |
MathKimi K2 wins3 benchmarks
Multimodal2 benchmarks
Inst. Following1 benchmarks
| Benchmark | Kimi K2 | o3 | Result |
|---|---|---|---|
| AA-IFBenchSource | 41.5% | 71.4% | o3 leads |
Frequently Asked Questions (2)
Which is better, Kimi K2 or o3?
o3 is ahead on BenchLM's BenchAlign leaderboard, 47.89 to 27.19. The biggest single separator in this matchup is FrontierMath v2 (Tiers 1-3), where the scores are 21.404% and 18.685%.
Which is better for math, Kimi K2 or o3?
Kimi K2 has the edge for math in this comparison, averaging 16.1 versus 14.5. Inside this category, FrontierMath v2 (Tiers 1-3) is the benchmark that creates the most daylight between them.
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