Grok 4.20 Reasoning API
This is a reasoning model from X Ai with catalog id x-ai/grok-4.20-reasoning. It has input price $1.25 per 1M tokens and output price $2.50 per 1M tokens. Context window is unpublished in the catalog.
What is Grok 4.20 Reasoning API in NextModel?
This is a reasoning model from X Ai with catalog id x-ai/grok-4.20-reasoning. It has input price $1.25 per 1M tokens and output price $2.50 per 1M tokens. Context window is unpublished in the catalog.
grok-4-20-reasoning via NextModel: 256k-token context; $1.25 / 1M tokens in / $2.50 / 1M tokens out per 1M tokens. Capabilities: streaming.
Best use cases
- Call this id if you want a reasoning model at the listed input and output prices and can work without a published context window.
- It is a candidate when your workload is quality-focused and streaming is sufficient.
- You need the listed capabilities on this catalog entry.
When not to use
- Do not call this id if you need a published context length or first-party CacheSafety benchmarks.
- Skip it if you do not want reasoning behavior, because this id is a reasoning model with output price $2.50 per 1M tokens.
- A required number is unpublished in the catalog snapshot.
OpenAI-compatible code example
curl https://api.nextmodel.app/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $NEXTMODEL_API_KEY" \
-d '{"model":"x-ai/grok-4.20-reasoning","messages":[{"role":"user","content":"Reply with OK."}]}'Switching models only changes the model field.
Similar alternatives
grok-4-1-fast-non-reasoning via NextModel: 2M-token context; $0.2 / 1M tokens in / $0.5 / 1M tokens out per 1M tokens. Capabilities: streaming.
grok-4-1-fast-reasoning via NextModel: 2M-token context; $0.2 / 1M tokens in / $0.5 / 1M tokens out per 1M tokens. Capabilities: streaming.
grok-4-20-non-reasoning via NextModel: 256k-token context; $1.25 / 1M tokens in / $2.50 / 1M tokens out per 1M tokens. Capabilities: streaming.
Reading
Articles that explain grok-4-20-reasoning
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FAQ
grok-4-20-reasoning API questions
What model id do I send for Grok 4.20 Reasoning?
Send x-ai/grok-4.20-reasoning to https://api.nextmodel.app/v1 with your OpenAI SDK. If that id is missing from /v1/models, the page is stale.
What does the catalog list for price and context?
Grok 4.20 Reasoning is listed at $1.25 / 1M tokens input and $2.50 / 1M tokens output. Context window: not published in catalog.
What should I treat as unverified?
Do not call this id if you need a published context length or first-party CacheSafety benchmarks. Skip it if you do not want reasoning behavior, because this id is a reasoning model with output price $2.50 per 1M tokens.
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