Head-to-head · 2026
Grok 4.3 vs GPT-5.5
Verdict. GPT-5.5 is clearly the stronger model; Grok 4.3 delivers a large share of the capability at roughly a fifth of the price — the budget-frontier default.
| Grok 4.3 | GPT-5.5 | |
|---|---|---|
| Provider | xAI | OpenAI |
| Released | 2026-04-30 | 2026-04-23 |
| Context | 1M | 1M |
| Max output | — | 128K |
| Input /1M | $1.25 | $5.00 |
| Output /1M | $2.50 | $30.00 |
| Modalities | text, vision, video | text, vision, audio, video |
The analysis
Grok 4.3 is xAI’s value play: an Artificial Analysis Intelligence Index of 53 and GDPval-AA around 1500 at $1.25/$2.50 per 1M — the cheapest frontier-class price, with fast output and a 2M-token window. GPT-5.5 sits higher on intelligence (84.9% GDPval, 78.7% OSWorld) but costs $5/$30 and is tuned for the hardest agentic and computer-use work.
The decision is almost entirely about where the task sits on the value curve. For high-volume, cost-sensitive workloads where "good enough frontier" wins, Grok 4.3 is hard to beat on price-per-intelligence. For the steps where capability is the bottleneck — autonomous computer use, the hardest coding — GPT-5.5 earns its premium.
A common pattern: Grok 4.3 as the cost-anchored default runtime, GPT-5.5 reserved for the critical path.
Pick Grok 4.3 if…
- Cheapest frontier-class intelligence ($1.25/$2.50)
- High-volume workloads where cost compounds
- 2M context and fast output matter
Pick GPT-5.5 if…
- You need the stronger model on hard agentic tasks
- Computer-use / OSWorld automation
- Native voice and broad multimodal
Grok 4.3
Fourth-best frontier intelligence at roughly the cheapest frontier price, with the fastest output in its tier.
GPT-5.5
OpenAI’s agentic flagship: best-in-class computer-use and knowledge-work scores, at double the price.