Pricing per million tokens, context window, capabilities — pulled from each provider's public docs. All 2 are available via the same AIgateway OpenAI-compatible endpoint; flip the model string to switch.
xAI Grok 4 Fast — low-latency variant.
xAI's Grok 4.20 reasoning model. Uses extended thinking to work through complex problems, returning a reasoning trace alongside the final answer.
from openai import OpenAI
client = OpenAI(
base_url="https://api.aigateway.sh/v1",
api_key="sk-aig-...",
)
# Grok 4 Fast
client.chat.completions.create(
model="xai/grok-4-fast",
messages=[{"role":"user","content":"hello"}],
)
# Grok 4.20 Reasoning
client.chat.completions.create(
model="xai/grok-4.20-0309-reasoning",
messages=[{"role":"user","content":"hello"}],
)