Grok 2 vs o4
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
Updated
Grok 2 specs · o4 specs- PriceTie
Neither model publishes per-token API pricing.
- Context windowo4
o4 accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.
- BenchmarksTie
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.
- ModalitiesTie
Both handle text, vision.
- OpennessTie
Both are closed-weight, API-only.
On balance o4 edges ahead, winning 1 of 5 categories against Grok 2's 0. Neither model publishes per-token API pricing. o4 accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. Both target the same set of modalities (text, vision), so the deciding factors are price, context, and raw quality. Both are closed-weight, API-only.
o4 is the newer of the two, released 16 months after Grok 2, which usually means a more recent knowledge cutoff and updated safety post-training. Grok 2 is usually picked for chatbots workloads, while o4 sees more deployments in reasoning and math. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | Grok 2 | o4 |
|---|---|---|
| Provider | xAI | OpenAI |
| Released | Aug 2024 | Dec 2025 |
| Modalities | text, vision | text, vision |
| Context window | 128K tokens | 200K tokens |
| Max output | , | , |
| Input · 1M | Pricing not published | Pricing not published |
| Output · 1M | Pricing not published | Pricing not published |
| Knowledge cutoff | , | , |
| Open weights | No | No |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day, vs ,
- Heavy usage, 1M in / 500k out per day, vs ,
- RAG workload, 5M in / 200k out per day, vs ,
Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- Grok 2Pricing unavailable
- o4Pricing unavailable
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
Grok 2 fits when…
- Free on X Premium
- Real-time data
o4 fits when…
- Exceptional performance on hard math and reasoning benchmarks
- Good at multi-step planning and verification
- Strong scientific reasoning
- Long-context tasks, handles 200K tokens vs 128K for Grok 2.
Consider Grok 4
xAI's mid-2025 flagship, top scores on Humanity's Last Exam at launch, with native real-time X integration.
Frequently asked
Is Grok 2 or o4 cheaper?
Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.Which has the larger context window?
o4 accepts 200K tokens vs 128K for Grok 2.Is Grok 2 or o4 better for coding?
Both Grok 2 and o4 are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
Neither model ships open weights, both are accessible only via their respective providers' APIs.When were Grok 2 and o4 released?
Grok 2 was released by xAI on 2024-08-13. o4 was released by OpenAI on 2025-12-15.
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