Grok 4 vs o3 Mini
Grok 4 (2026) and o3 Mini (2025) are frontier-tier reasoning models from xAI and OpenAI. Grok 4 ships a 256k-token context window, while o3 Mini ships a not-yet-sourced context window. On MMLU PRO, Grok 4 leads by 7.9 pts. On pricing, o3 Mini costs $1.1/1M input tokens versus $3/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.
o3 Mini is ~173% cheaper at $1.1/1M; pay for Grok 4 only for coding workflow support.
Specs
Pricing and availability
| Grok 4 | o3 Mini | |
|---|---|---|
| Input price | $3/1M tokens | $1.1/1M tokens |
| Output price | $15/1M tokens | $4.4/1M tokens |
| Providers |
Capabilities
| Grok 4 | o3 Mini | |
|---|---|---|
| Vision | ||
| Multimodal | ||
| Reasoning | ||
| Function calling | ||
| Tool use | ||
| Structured outputs | ||
| Code execution |
Benchmarks
| Benchmark | Grok 4 | o3 Mini |
|---|---|---|
| MMLU PRO | 87.0 | 79.1 |
| Aider Polyglot | 79.6 | 60.4 |
Deep dive
On shared benchmark coverage, MMLU PRO has Grok 4 at 87 and o3 Mini at 79.1, with Grok 4 ahead by 7.9 points; Aider Polyglot has Grok 4 at 79.6 and o3 Mini at 60.4, with Grok 4 ahead by 19.2 points. The largest visible gap is 19.2 points on Aider Polyglot, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on multimodal input: Grok 4, function calling: o3 Mini, and tool use: o3 Mini. Both models share reasoning mode, structured outputs, and code execution, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, Grok 4 lists $3/1M input and $15/1M output tokens, while o3 Mini lists $1.1/1M input and $4.4/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts o3 Mini lower by about $4.51 per million blended tokens. Availability is 3 providers versus 3, so concentration risk also matters.
Choose Grok 4 when coding workflow support are central to the workload. Choose o3 Mini when coding workflow support and lower input-token cost are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which is cheaper, Grok 4 or o3 Mini?
o3 Mini is cheaper on tracked token pricing. Grok 4 costs $3/1M input and $15/1M output tokens. o3 Mini costs $1.1/1M input and $4.4/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Grok 4 or o3 Mini open source?
Grok 4 is listed under Proprietary. o3 Mini is listed under Unknown. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for multimodal input, Grok 4 or o3 Mini?
Grok 4 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for reasoning mode, Grok 4 or o3 Mini?
Both Grok 4 and o3 Mini expose reasoning mode. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for function calling, Grok 4 or o3 Mini?
o3 Mini has the clearer documented function calling signal in this comparison. If function calling is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run Grok 4 and o3 Mini?
Grok 4 is available on Microsoft Foundry, OpenRouter, and Replicate API. o3 Mini is available on OpenRouter, OpenAI Batch API, and Azure OpenAI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-04-24. Data sourced from public model cards and provider documentation.