GPT-5.4 mini vs Grok 4.20 (Reasoning) vs Grok 4.3
Too close to call on our weighted score (Grok 4.20 (Reasoning) 68, Grok 4.3 67, GPT-5.4 mini 63). The right pick depends on what you value most.
OpenAIGPT-5.4 mini
63/100- ECI148.8
- Price$0.75 / $4.50
- Context400K
xAIGrok 4.20 (Reasoning)
68/100- ECI152.0
- Price$1.25 / $2.50
- Context1M
- xAI
Grok 4.3
67/100- ECI149.2
- Price$1.25 / $2.50
- Context1M
Too close to call
It is close. Our weighted score puts them within 2 points (Grok 4.20 (Reasoning) 68/100, Grok 4.3 67/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Grok 4.20 (Reasoning) for raw capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityGrok 4.20 (Reasoning)Capabilities Index (ECI): Grok 4.20 (Reasoning) 152.0 · Grok 4.3 149.2 · GPT-5.4 mini 148.8
- Lowest priceGrok 4.20 (Reasoning) and Grok 4.3Grok 4.20 (Reasoning) $1.56 · Grok 4.3 $1.56 · GPT-5.4 mini $1.69 per 1M tokens (3:1 blend)
- Longest contextGrok 4.20 (Reasoning) and Grok 4.3Grok 4.20 (Reasoning) 1,000,000 · Grok 4.3 1,000,000 · GPT-5.4 mini 400,000 tokens
- Widest inputsGrok 4.20 (Reasoning) and Grok 4.3GPT-5.4 mini: Text, Images · Grok 4.20 (Reasoning): Text, Images, PDFs · Grok 4.3: Text, Images, PDFs
- Self-hostingNo open weightsAll three are available only through APIs
| Measure | Weight | GPT-5.4 mini | Grok 4.20 (Reasoning) | Grok 4.3 |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 77 | 81 | 77 |
| Price | 25% | 39 | 41 | 41 |
| Inputs & features | 15% | 70 | 80 | 80 |
| Context window | 10% | 44 | 60 | 60 |
| Overall | 100% | 63/100 | 68/100 | 67/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | GPT-5.4 miniOpenAI | Grok 4.20 (Reasoning)xAI | Grok 4.3xAI |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 148.8 | 152.0 (best) | 149.2 |
| ECI rank | #56 of 148 | #41 of 148 (best) | #55 of 148 |
| GPQA DiamondGraduate-level science questions | 86.9% | 89.3% (best) | 88.8% |
| FrontierMath Tiers 1–3Research-level mathematics | 51.2% (best) | 44.9% | 42.8% |
| OTIS Mock AIME 2024–2025Competition mathematics | 88.9% | 92.2% | 93.3% (best) |
| SimpleQA VerifiedShort factual questions | 29.4% | 30.2% | 33.2% (best) |
| Price per million tokens | |||
| Input | $0.75 (best) | $1.25 | $1.25 |
| Output | $4.50 | $2.50 (best) | $2.50 (best) |
| Cached input | $0.075 (best) | $0.20 | $0.20 |
| Blended (3:1) | $1.69 | $1.56 (best) | $1.56 (best) |
| Long-context rate | Same rate | Over 200K: $2.50 / $5.00 | Over 200K: $2.50 / $5.00 |
| Price source | Official OpenAI API | Official xAI API | Official xAI API |
| Limits | |||
| Context window | 400,000 tokens | 1,000,000 tokens (best) | 1,000,000 tokens (best) |
| Max output | 128,000 tokens (best) | 30,000 tokens | 30,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | No | Yes | Yes |
| Audio | No | No | No |
| Video | No | No | No |
| Reasoning | Yeslow · medium · high · xhigh | Yes | Yeslow · medium · high |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | Yes |
| Availability | |||
| Weights | Proprietary | Proprietary | Proprietary |
| API model ID | gpt-5.4-mini | grok-4.20-0309-reasoning | grok-4.3 |
| API providers | 29 (best) | 11 | 27 |
| Released | Mar 17, 2026 | Mar 9, 2026 | Apr 17, 2026 |
| Knowledge cutoff | 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.
- GPT-5.4 mini$16.50
- Grok 4.20 (Reasoning)$17.50
- Grok 4.3$17.50
Which should you choose?
Which is better: GPT-5.4 mini, Grok 4.20 (Reasoning) or Grok 4.3?
It is close. Our weighted score puts them within 2 points (Grok 4.20 (Reasoning) 68/100, Grok 4.3 67/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Grok 4.20 (Reasoning) for raw capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, GPT-5.4 mini, Grok 4.20 (Reasoning) or Grok 4.3?
Grok 4.20 (Reasoning) is cheaper at $1.25 input / $2.50 output per million tokens (official xAI API price). Grok 4.3 costs $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). At a typical mix of three input tokens to one output token, that is $1.56 per million tokens for Grok 4.20 (Reasoning) versus $1.56 for Grok 4.3 (1× as much) and $1.69 for GPT-5.4 mini (1.1× as much).
Which scores higher on benchmarks?
Grok 4.20 (Reasoning) scores higher on the Capabilities Index (ECI): Grok 4.20 (Reasoning) 152.0 (#41 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 (149.3–154.4 vs 147.6–150.8), so treat the gap as small. On individual benchmarks: GPQA Diamond — Grok 4.20 (Reasoning) 89.3%, Grok 4.3 88.8%, GPT-5.4 mini 86.9%; FrontierMath Tiers 1–3 — GPT-5.4 mini 51.2%, Grok 4.20 (Reasoning) 44.9%, Grok 4.3 42.8%; OTIS Mock AIME 2024–2025 — Grok 4.3 93.3%, Grok 4.20 (Reasoning) 92.2%, GPT-5.4 mini 88.9%; SimpleQA Verified — Grok 4.3 33.2%, Grok 4.20 (Reasoning) 30.2%, GPT-5.4 mini 29.4%.
Which is better for coding?
There are no published SWE-bench Verified results for GPT-5.4 mini, Grok 4.20 (Reasoning) and Grok 4.3 yet, so there is no like-for-like coding score. On overall capability, Grok 4.20 (Reasoning) 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 4.20 (Reasoning) and Grok 4.3 have the largest context windows (1,000,000 and 1,000,000 tokens), against 400,000 for GPT-5.4 mini. Maximum output per response: GPT-5.4 mini up to 128,000, Grok 4.20 (Reasoning) up to 30,000, Grok 4.3 up to 30,000 tokens.
Which can read images, PDFs, audio or video?
GPT-5.4 mini accepts text and images; Grok 4.20 (Reasoning) accepts text, images and PDFs; Grok 4.3 accepts text, images and PDFs. Grok 4.20 (Reasoning) handles the widest range of inputs.
Are any of these open source?
No. GPT-5.4 mini, Grok 4.20 (Reasoning) and Grok 4.3 are proprietary and only available through APIs and apps.
Which is newer?
Grok 4.3 is the newest, released Apr 17, 2026. GPT-5.4 mini came out Mar 17, 2026; Grok 4.20 (Reasoning) came out Mar 9, 2026. Knowledge cutoff: 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.
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