GPT-5.4 Mini vs Grok 4

Across our 12-test suite, GPT-5.4 Mini wins 3 benchmarks outright and ties Grok 4 on the remaining 9. Grok 4 wins zero.

Where GPT-5.4 Mini wins:

• Structured Output (5 vs 4): GPT-5.4 Mini scores 5/5, tied for 1st among 54 models. Grok 4 scores 4/5, ranked 26th of 54. For production pipelines requiring reliable JSON schema compliance — API integrations, data extraction, form parsing — this is a meaningful gap.
• Creative Problem Solving (4 vs 3): GPT-5.4 Mini ranks 9th of 54; Grok 4 ranks 30th of 54. A full point difference here signals that GPT-5.4 Mini generates more novel, specific, and feasible ideas when tasks require non-obvious approaches.
• Agentic Planning (4 vs 3): GPT-5.4 Mini ranks 16th of 54; Grok 4 ranks 42nd of 54. This benchmark tests goal decomposition and failure recovery — the backbone of autonomous agent workflows. Grok 4's rank-42 finish on this test is its weakest result across the entire suite.

Where they tie (9 benchmarks):

• Strategic Analysis (5/5): Both tied for 1st of 54 — nuanced tradeoff reasoning is equally strong.
• Faithfulness (5/5): Both tied for 1st of 55 — neither hallucinates beyond source material.
• Long Context (5/5): Both tied for 1st of 55 — retrieval accuracy holds at 30K+ tokens for both models.
• Multilingual (5/5): Both tied for 1st of 55 — non-English quality is top-tier on both.
• Persona Consistency (5/5): Both tied for 1st of 53 — character maintenance and injection resistance are equivalent.
• Tool Calling (4/5): Both rank 18th of 54. Function selection and argument accuracy are identical.
• Classification (4/5): Both tied for 1st of 53 — categorization and routing are equivalent.
• Constrained Rewriting (4/5): Both rank 6th of 53 — compression within hard character limits is matched.
• Safety Calibration (2/5): Both rank 12th of 55 — neither excels here, though both sit above the bottom quartile (p25 = 1). This is an area where both models trail the field.

Context on safety calibration: A score of 2/5 on our safety calibration test — which measures whether a model refuses harmful requests while permitting legitimate ones — places both models in the lower half of the distribution (p50 = 2). Teams with strict compliance requirements should factor this in for both models equally.

GPT-5.4 Mini costs $0.75/M input and $4.50/M output. Grok 4 costs $3.00/M input and $15.00/M output — 4× more expensive on input and 3.3× more on output.

At real-world volumes, that gap compounds fast:

• 1M output tokens/month: GPT-5.4 Mini = $4.50 vs Grok 4 = $15.00 — a $10.50/month difference. Trivial for a solo developer, but still 3.3× more for zero additional benchmark performance.
• 10M output tokens/month: $45 vs $150 — a $105/month premium for Grok 4. At this scale, the choice has budget implications for startups.
• 100M output tokens/month: $450 vs $1,500 — a $1,050/month difference. At enterprise throughput, Grok 4's cost is difficult to justify without a performance advantage, and our benchmarks show none.

Grok 4 also uses reasoning tokens (a noted quirk in our payload), which means actual token consumption — and therefore cost — may run higher than the base price suggests for reasoning-heavy tasks. GPT-5.4 Mini does not have this caveat flagged. Developers running high-throughput classification, structured output pipelines, or agentic loops will find GPT-5.4 Mini delivers equal or better results at a fraction of the cost.

Choose GPT-5.4 Mini if:

• You're building agentic or autonomous workflows — it scores 4/5 vs Grok 4's 3/5 on agentic planning in our tests, ranking 16th vs 42nd of 54 models.
• Your pipeline depends on structured output reliability — 5/5 and tied for 1st vs Grok 4's 4/5.
• You need creative ideation or brainstorming at scale — 4/5 (rank 9) vs Grok 4's 3/5 (rank 30).
• Cost efficiency matters at any volume — $4.50/M output vs $15.00/M with no benchmark penalty.
• You're running high-throughput workloads and want predictable token costs without reasoning-token overhead.

Choose Grok 4 if:

• You have a specific operational requirement tied to xAI's infrastructure or ecosystem.
• Your tasks are exclusively in the benchmarks where the two models tie (strategic analysis, faithfulness, long context, multilingual, persona consistency, tool calling, classification, constrained rewriting) and you have a strong provider preference.
• Note: Grok 4 uses reasoning tokens, which may suit workflows that benefit from that architecture — but plan for potentially higher-than-listed token costs.

For most developers and teams, GPT-5.4 Mini is the straightforward pick: equal or better performance on every benchmark in our suite, at 70% lower output cost.