Grok 4 vs OpenAI o3
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Grok 4
xAI · Jul 2025
xAI's mid-2025 flagship, trained on the 200K-GPU Colossus cluster — a math and science reasoning standout of its generation.
OpenAI o3
68.9OpenAI · Apr 2025
OpenAI's dedicated 2025 reasoning model that pioneered thinking-with-images and agentic tool use within chain-of-thought.
The verdict
Grok 4 wins 3 of the 3 benchmarks these models share, against 0 for OpenAI o3. OpenAI o3 is about 1.7x cheaper per blended million tokens (3:1 input:output mix). Grok 4 also takes 256K of context versus 200K for OpenAI o3.
Benchmark head-to-head 3–0
Specs & pricing
| Grok 4 | OpenAI o3 | |
|---|---|---|
| modhub Index | — | 68.9 |
| Input price / 1M | $3 | $2 |
| Output price / 1M | $15 | $8 |
| Context window | 256K | 200K |
| Max output | — | 100K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Jul 2025 | May 2024 |
| Released | Jul 2025 | Apr 2025 |
| Example monthly cost* | $52.50 | $32.00 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Grok 4 or OpenAI o3?
- Grok 4 wins 3 of the 3 benchmarks these models share, against 0 for OpenAI o3. OpenAI o3 is about 1.7x cheaper per blended million tokens (3:1 input:output mix). Grok 4 also takes 256K of context versus 200K for OpenAI o3.
- Which is cheaper, Grok 4 or OpenAI o3?
- Grok 4 costs $3/$15 per million input/output tokens, while OpenAI o3 costs $2/$8. For a typical workload of 10M input and 1.5M output tokens per month, that's $52.50 versus $32.00.
- Which model is better for coding, Grok 4 or OpenAI o3?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.