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Grok 4.20 (0309) Reasoning

GA

Reasoning-optimized variant. Aliases include grok-4.20-reasoning-latest, grok-4.20, grok-4.20-reasoning. Modality 'text, image -> text' per official model page. Pricing and cached-input ($0.20/M) confirmed on official model page. Max output tokens, knowledge cutoff and release date not published on docs. Note: docs warn no logprobs support for grok-4.20+.

Grok 4.20 (0309) Reasoning by xAI costs $1.25 per 1M input tokens and $2.50 per 1M output tokens ($1.56/1M blended), with a 1M (1.000.000-token) context window. It is generally available (GA).

Last verified: 13 Aug 2026 · sourced from official provider documentation

Provider
xAI
Status
GA
Input price
$1.25 / 1M tokens
Output price
$2.50 / 1M tokens
Cached input
$0.2 / 1M tokens
Blended price
$1.56 / 1M tokens
Context window
1.000.000 tokens (1M)
Max output
—
Modality
text-in, image-in, text-out
Open weights
No — API only
Knowledge cutoff
—
Released
—
API string
grok-4.20-0309-reasoning

Source: xAI official documentation ↗

See also

Compare Grok 4.20 (0309) Reasoning head-to-head

Grok 4.20 (0309) Reasoning vs Grok 4.20 (0309) Non-Reasoning→

$1.56 vs $1.56 blended /M · same family

Grok 4.20 (0309) Reasoning vs Grok 4.3→

$1.56 vs $1.56 blended /M · same family

Grok 4.20 (0309) Reasoning vs Grok 4.5→

$1.56 vs $3 blended /M · same family

FAQ

Grok 4.20 (0309) Reasoning — questions & answers

How much does Grok 4.20 (0309) Reasoning cost?

Grok 4.20 (0309) Reasoning is priced at $1.25 per 1M input tokens and $2.50 per 1M output tokens ($1.56/1M blended at a 3:1 input-to-output ratio), with cached input at $0.2 per 1M tokens.

What is the context window of Grok 4.20 (0309) Reasoning?

Grok 4.20 (0309) Reasoning has a 1.000.000-token context window (1M).

Is Grok 4.20 (0309) Reasoning deprecated?

No — Grok 4.20 (0309) Reasoning is generally available (GA) and not currently scheduled for deprecation or retirement in our tracker.

Does Grok 4.20 (0309) Reasoning support image or vision input?

Yes — Grok 4.20 (0309) Reasoning accepts image input. Listed modalities: text-in, image-in, text-out.

Can I self-host Grok 4.20 (0309) Reasoning?

No — Grok 4.20 (0309) Reasoning is proprietary. Its weights are not publicly released, so it is available only through xAI's API (or hosted partners), not for self-hosting.

What is the API model string for Grok 4.20 (0309) Reasoning?

The API model identifier for Grok 4.20 (0309) Reasoning is "grok-4.20-0309-reasoning" when calling xAI's API.