Grok 4.3 vs Kimi K2.6 vs GPT-5.4 mini
Too close to call on our weighted score (Grok 4.3 67, Kimi K2.6 65, GPT-5.4 mini 63). The right pick depends on what you value most.
xAIGrok 4.3
67/100- ECI149.2
- Price$1.25 / $2.50
- Context1M
Moonshot AIKimi K2.6
65/100- ECI151.1
- Price$0.95 / $4.00
- Context262K
OpenAIGPT-5.4 mini
63/100- ECI148.8
- Price$0.75 / $4.50
- Context400K
Too close to call
It is close. Our weighted score puts them within 2 points (Grok 4.3 67/100, Kimi K2.6 65/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Kimi K2.6 for raw capability, Grok 4.3 on price and Grok 4.3 for long inputs. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityKimi K2.6Capabilities Index (ECI): Kimi K2.6 151.1 · Grok 4.3 149.2 · GPT-5.4 mini 148.8
- Lowest priceGrok 4.3Grok 4.3 $1.56 · GPT-5.4 mini $1.69 · Kimi K2.6 $1.71 per 1M tokens (3:1 blend)
- Longest contextGrok 4.3Grok 4.3 1,000,000 · GPT-5.4 mini 400,000 · Kimi K2.6 262,144 tokens
- Widest inputsGrok 4.3 and Kimi K2.6Grok 4.3: Text, Images, PDFs · Kimi K2.6: Text, Images, Video · GPT-5.4 mini: Text, Images
- Self-hostingKimi K2.6Publishes downloadable weights
| Measure | Weight | Grok 4.3 | Kimi K2.6 | GPT-5.4 mini |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 77 | 79 | 77 |
| Price | 25% | 41 | 39 | 39 |
| Inputs & features | 15% | 80 | 80 | 70 |
| Context window | 10% | 60 | 37 | 44 |
| Overall | 100% | 67/100 | 65/100 | 63/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Grok 4.3xAI | Kimi K2.6Moonshot AI | GPT-5.4 miniOpenAI |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 149.2 | 151.1 (best) | 148.8 |
| ECI rank | #55 of 148 | #45 of 148 (best) | #56 of 148 |
| GPQA DiamondGraduate-level science questions | 88.8% | 90.8% (best) | 86.9% |
| FrontierMath Tiers 1–3Research-level mathematics | 42.8% | 57.2% (best) | 51.2% |
| OTIS Mock AIME 2024–2025Competition mathematics | 93.3% | 96.1% (best) | 88.9% |
| SWE-bench VerifiedFixing real GitHub issues | — | 76.7% | — |
| SimpleQA VerifiedShort factual questions | 33.2% | 34.9% (best) | 29.4% |
| Price per million tokens | |||
| Input | $1.25 | $0.95 | $0.75 (best) |
| Output | $2.50 (best) | $4.00 | $4.50 |
| Cached input | $0.20 | $0.16 | $0.075 (best) |
| Blended (3:1) | $1.56 (best) | $1.71 | $1.69 |
| Long-context rate | Over 200K: $2.50 / $5.00 | Same rate | Same rate |
| Price source | Official xAI API | Official Moonshot AI API | Official OpenAI API |
| Limits | |||
| Context window | 1,000,000 tokens (best) | 262,144 tokens | 400,000 tokens |
| Max output | 30,000 tokens | 262,144 tokens (best) | 128,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | Yes | No | No |
| Audio | No | No | No |
| Video | No | Yes | No |
| Reasoning | Yeslow · medium · high | Yes | Yeslow · medium · high · xhigh |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | Yes |
| Availability | |||
| Weights | Proprietary | Open | Proprietary |
| API model ID | grok-4.3 | kimi-k2.6 | gpt-5.4-mini |
| API providers | 27 | 46 (best) | 29 |
| Released | Apr 17, 2026 | Apr 21, 2026 | Mar 17, 2026 |
| Knowledge cutoff | — | Jan 2025 | Aug 31, 2025 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Grok 4.3$17.50
- Kimi K2.6$17.50
- GPT-5.4 mini$16.50
Which should you choose?
Which is better: Grok 4.3, Kimi K2.6 or GPT-5.4 mini?
It is close. Our weighted score puts them within 2 points (Grok 4.3 67/100, Kimi K2.6 65/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Kimi K2.6 for raw capability, Grok 4.3 on price and Grok 4.3 for long inputs. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, Grok 4.3, Kimi K2.6 or GPT-5.4 mini?
Grok 4.3 is cheaper at $1.25 input / $2.50 output per million tokens (official xAI API price). GPT-5.4 mini costs $0.75 input / $4.50 output per million tokens (official OpenAI API price); Kimi K2.6 costs $0.95 input / $4.00 output per million tokens (official Moonshot AI API price). At a typical mix of three input tokens to one output token, that is $1.56 per million tokens for Grok 4.3 versus $1.69 for GPT-5.4 mini (1.1× as much) and $1.71 for Kimi K2.6 (1.1× as much).
Which scores higher on benchmarks?
Kimi K2.6 scores higher on the Capabilities Index (ECI): Kimi K2.6 151.1 (#45 of 148), Grok 4.3 149.2 (#55 of 148) and GPT-5.4 mini 148.8 (#56 of 148). The confidence ranges of the top two overlap (149.1–152.8 vs 147.6–150.8), so treat the gap as small. On individual benchmarks: GPQA Diamond — Kimi K2.6 90.8%, Grok 4.3 88.8%, GPT-5.4 mini 86.9%; FrontierMath Tiers 1–3 — Kimi K2.6 57.2%, GPT-5.4 mini 51.2%, Grok 4.3 42.8%; OTIS Mock AIME 2024–2025 — Kimi K2.6 96.1%, Grok 4.3 93.3%, GPT-5.4 mini 88.9%; SimpleQA Verified — Kimi K2.6 34.9%, Grok 4.3 33.2%, GPT-5.4 mini 29.4%.
Which is better for coding?
There are no published SWE-bench Verified results for Grok 4.3 and GPT-5.4 mini yet, so there is no like-for-like coding score. On overall capability, Kimi K2.6 leads, which tends to carry over to coding, but test on your own codebase. All three support tool calling for agent workflows.
Which has the bigger context window?
Grok 4.3 has the largest context window at 1,000,000 tokens, against 400,000 for GPT-5.4 mini and 262,144 for Kimi K2.6. Maximum output per response: Grok 4.3 up to 30,000, Kimi K2.6 up to 262,144, GPT-5.4 mini up to 128,000 tokens.
Which can read images, PDFs, audio or video?
Grok 4.3 accepts text, images and PDFs; Kimi K2.6 accepts text, images and video; GPT-5.4 mini accepts text and images. Grok 4.3 handles the widest range of inputs.
Are any of these open source?
Kimi K2.6 publishes its weights and can be self-hosted; Grok 4.3 and GPT-5.4 mini is proprietary.
Which is newer?
Kimi K2.6 is the newest, released Apr 21, 2026. Grok 4.3 came out Apr 17, 2026; GPT-5.4 mini came out Mar 17, 2026. Knowledge cutoff: Kimi K2.6 Jan 2025, GPT-5.4 mini Aug 31, 2025.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
Related comparisons
- Grok 4.3 vs Kimi K2.7 CodeMoonshot AI · ECI 150.0
- Grok 4.3 vs GLM-5.1Z.ai (Zhipu) · ECI 149.9
- Grok 4.3 vs Qwen3.6 Max PreviewAlibaba (Qwen) · ECI 149.2
- Kimi K2.6 vs Grok 4.20 (Reasoning)xAI · ECI 152.0
- Kimi K2.6 vs GLM-5.1Z.ai (Zhipu) · ECI 149.9
- Kimi K2.6 vs Qwen3.6 Max PreviewAlibaba (Qwen) · ECI 149.2
