Grok 4.3 vs OpenAI o3
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Grok 4.3
xAI · Apr 2026
xAI's frontier model: 1M context at $1.25/$2.50, ~168 tokens/sec, and a record low hallucination rate on independent testing.
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
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. Grok 4.3 is about 2.2x cheaper per blended million tokens (3:1 input:output mix). Grok 4.3 also takes 1M of context versus 200K for OpenAI o3.
Specs & pricing
| Grok 4.3 | OpenAI o3 | |
|---|---|---|
| modhub Index | — | 68.9 |
| Input price / 1M | $1.25 | $2 |
| Output price / 1M | $2.5 | $8 |
| Context window | 1M | 200K |
| Max output | — | 100K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Mar 2026 | May 2024 |
| Released | Apr 2026 | Apr 2025 |
| Example monthly cost* | $16.25 | $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 4.3 or OpenAI o3?
- These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. Grok 4.3 is about 2.2x cheaper per blended million tokens (3:1 input:output mix). Grok 4.3 also takes 1M of context versus 200K for OpenAI o3.
- Which is cheaper, Grok 4.3 or OpenAI o3?
- Grok 4.3 costs $1.25/$2.5 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 $16.25 versus $32.00.
- Which model is better for coding, Grok 4.3 or OpenAI o3?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.