Grok-3 vs o3 Mini
Grok-3 (2025) and o3 Mini (2025) are frontier-tier reasoning models from xAI and OpenAI. Grok-3 ships a 131k-token context window, while o3 Mini ships a 200k-token context window. On MMLU PRO, Grok-3 leads by 0.8 pts. On pricing, Grok-3 costs $0.80/1M input tokens versus $1.10/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Grok-3 is safer overall; choose o3 Mini when coding workflow support matters.
Decision scorecard
Local evidence first| Signal | Grok-3 | o3 Mini |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps, tool-calling agents, and provider-routed production |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 131k | 200k |
| Cheapest output | $2.40/1M tokens | $4.40/1M tokens |
| Provider routes | 4 tracked | 4 tracked |
| Shared benchmarks | MMLU PRO leader | 4 rows |
Decision tradeoffs
- Grok-3 holds a shared-benchmark lead on MMLU PRO, ahead by 0.8 points.
- Grok-3 has the lower cheapest tracked output price at $2.40/1M tokens.
- Grok-3 uniquely exposes Vision and Multimodal in local model data.
- Local decision data tags Grok-3 for Coding, RAG, and Agents.
- o3 Mini holds a shared-benchmark lead on Aider Polyglot, ahead by 7.1 points.
- o3 Mini has the larger context window for long prompts, retrieval packs, or transcript analysis.
- o3 Mini uniquely exposes Code execution in local model data.
- Local decision data tags o3 Mini for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Grok-3
$1,240
Cheapest tracked route/tier: Chutes AI
o3 Mini
$1,980
Cheapest tracked route/tier: OpenRouter
Estimated monthly gap: $740. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- o3 Mini is $2.00/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Vision and Multimodal before moving production traffic.
- o3 Mini adds Code execution in local capability data.
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- Grok-3 is $2.00/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Code execution before moving production traffic.
- Grok-3 adds Vision and Multimodal in local capability data.
Specs
Pricing and availability
| Pricing attribute | Grok-3 | o3 Mini |
|---|---|---|
| Input price | $0.80/1M tokens | $1.10/1M tokens |
| Output price | $2.40/1M tokens | $4.40/1M tokens |
| Providers |
Capabilities
| Capability | Grok-3 | o3 Mini |
|---|---|---|
| Vision | Yes | No |
| Multimodal | Yes | No |
| Reasoning | Yes | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | No | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Grok-3 | o3 Mini |
|---|---|---|
| MMLU PRO | 79.9 | 79.1 |
| Google-Proof Q&A | 84.6 | 79.7 |
| Chatbot Arena | 1405.0 | 1335.0 |
| Aider Polyglot | 53.3 | 60.4 |
Deep dive
On shared benchmark coverage, MMLU PRO has Grok-3 at 79.9 and o3 Mini at 79.1, with Grok-3 ahead by 0.8 points; Google-Proof Q&A has Grok-3 at 84.6 and o3 Mini at 79.7, with Grok-3 ahead by 4.9 points; Chatbot Arena has Grok-3 at 1405 and o3 Mini at 1335, with Grok-3 ahead by 70 points. The largest visible gap is 70 points on Chatbot Arena, 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 vision: Grok-3, multimodal input: Grok-3, and code execution: o3 Mini. Both models share reasoning mode, function calling, tool use, and structured outputs, 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-3 lists $0.80/1M input and $2.40/1M output tokens on the cheapest tracked provider, while o3 Mini lists $1.10/1M input and $4.40/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Grok-3 lower by about $0.81 per million blended tokens. Availability is 4 providers versus 4, so concentration risk also matters.
Choose Grok-3 when vision-heavy evaluation and lower input-token cost are central to the workload. Choose o3 Mini when coding workflow support and larger context windows are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Grok-3 or o3 Mini?
o3 Mini supports 200k tokens, while Grok-3 supports 131k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is cheaper, Grok-3 or o3 Mini?
Grok-3 is cheaper on tracked token pricing. Grok-3 costs $0.80/1M input and $2.40/1M output tokens. o3 Mini costs $1.10/1M input and $4.40/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Grok-3 or o3 Mini open source?
Grok-3 is listed under Proprietary. o3 Mini is listed under Proprietary. 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 vision, Grok-3 or o3 Mini?
Grok-3 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, Grok-3 or o3 Mini?
Grok-3 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.
Where can I run Grok-3 and o3 Mini?
Grok-3 is available on OpenRouter, xAI Console, Chutes AI, and Microsoft Foundry. o3 Mini is available on OpenRouter, Azure OpenAI, OpenAI API, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-06-04. Data sourced from public model cards and provider documentation.