Grok 4 Fast (Reasoning) API Pricing

SpaceXAI · released 2025-09-19

Pricing

$0.20
input / 1M tokens
0.020¢ / 1K
$0.50
output / 1M tokens
0.050¢ / 1K
$0.275
blended / 1M tokens
0.028¢ / 1K

What it actually costs

WorkloadTokensCost
Short chat reply500 in / 300 out0.025¢
RAG query4,000 in / 500 out0.105¢
Long document summary50,000 in / 1,000 out$0.0105
Code review of a 2k-line file30,000 in / 2,000 out0.7¢
1,000 chat replies/day for 30 days30,000 × (500 in / 300 out)$7.50

Cost = (input tokens ÷ 1,000,000 × $0.20) + (output tokens ÷ 1,000,000 × $0.50).

Benchmarks

17.9
Intelligence
#145 of 533
Coding
89.7
Math
#23 of 249
Tokens/sec
Time to first token

Similar intelligence, lower price

ModelIntelligenceBlended $/1M
MiMo-V2-Flash (Reasoning)20.8$0.15
Step 3.5 Flash 260317.0$0.15
Step 3.5 Flash16.6$0.15
GLM-4.7-Flash (Reasoning)14.9$0.153
Gemma 4 26B A4B (Reasoning)16.7$0.179

Leaderboard neighbours

ModelIntelligenceBlended $/1M
GLM-4.6 (Reasoning)18.5$0.963
Qwen3.6 35B A3B (Reasoning)18.2$0.844
Gemini 3 Flash Preview (Non-reasoning)17.9$1.125
Grok 4 Fast (Reasoning)17.9$0.275
Claude 3.7 Sonnet (Reasoning)17.7
Qwen3.5 122B A10B (Non-reasoning)17.7$1.10
Muse Glimmer (high)17.5$0.637

More from SpaceXAI

ModelIntelligenceBlended $/1M
Grok 4.7 (xhigh)46.4$3.00
Grok 4.6 (high)44.3$3.00
Grok 4.5 (high)38.8$3.00
Grok Build 0.1 061627.2$1.25
Grok 4.20 0309 v2 (Reasoning)25.7$1.563
Grok 4.20 0309 (Reasoning)25.2$3.00
Grok 4.3 (high)24.9$1.563
Grok 422.5$6.00

Count tokens & estimate cost for Grok 4 Fast (Reasoning) See Grok 4 Fast (Reasoning) on the leaderboard

Source: Artificial Analysis · last synced 2026-09-22

FAQ

Who develops Grok 4 Fast (Reasoning)?

Grok 4 Fast (Reasoning) is developed by SpaceXAI, released 2025-09-19.

How much does Grok 4 Fast (Reasoning) cost per million tokens?

Grok 4 Fast (Reasoning) costs $0.20 per 1M input tokens and $0.50 per 1M output tokens ($0.275 blended), per Artificial Analysis's official pricing data.

How does Grok 4 Fast (Reasoning) rank on benchmarks?

Grok 4 Fast (Reasoning) scores 17.9 on the Artificial Analysis Intelligence Index, ranking #145 of 533 models we track.

Is there a cheaper model with similar intelligence to Grok 4 Fast (Reasoning)?

Yes — MiMo-V2-Flash (Reasoning) scores similar intelligence (20.8) at $0.15/1M blended, versus $0.275/1M for Grok 4 Fast (Reasoning).

Where does this data come from?

Pricing and benchmark data for Grok 4 Fast (Reasoning) comes from Artificial Analysis (artificialanalysis.ai), synced daily. Last synced 2026-09-22.