AllocateGPT-5.5 vs Grok 4.3
Grok 4.3 is not currently in the Allocate serving catalog, so this page lists no prices for it: every price on this site comes from the live catalog.
GPT-5.5
Grok 4.3LabOpenAIxAI
AccessAPI onlyNot served on Allocate
Context window400K tokensn/a
List price, input$5 / M tokensNot served
List price, output$30 / M tokensNot served
Cached input$0.5 / M tokensn/a
LicenseProprietary APIProprietary API
Fine-tunableNoNo
Specifications and provider list prices from the Allocate catalog, checked 2026-07-21.
Choose Grok 4.3 for
- Freshness-sensitive answers
- Fast reasoning turns
- Research assistants
Common questions
Which has the bigger context window?
GPT-5.5: 400,000 tokens (400K) against an unlisted window for Grok 4.3.
Can I fine-tune GPT-5.5 or Grok 4.3?
No. Both are closed models served over API. If you want a model you can train and own, start from an open-weights base in the catalog.
Related comparisons
Run the numbers on your workload
Or don’t choose. On Allocate a route name is the contract: point yours at one model today, swap to the other tomorrow, and compare them on your live traffic with per-token metering.