GPT-4o Mini vs Grok 3: Detailed Comparison

Choosing between GPT-4o Mini (OpenAI) and Grok 3 (xAI) comes down to three things: per-token pricing, context window, and which capability matters most for your workload. GPT-4o Mini costs $0.15/M input vs $3.00/M for Grok 3; context windows are 128K vs 1.0M tokens. Detailed breakdown below.

Side-by-side specs

SpecGPT-4o MiniGrok 3
ProviderOpenAIxAI
Released2024-07-182025-02-17
Input price $0.15/M $3.00/M
Output price $0.60/M $15.00/M
Cached input $0.0750/M
Context window 128K 1.0M
Max output 16K 16K
Modalities text image text image
Tokenizer o200k_base grok

Capability matrix

CapabilityGPT-4o MiniGrok 3
function calling Yes Yes
json mode Yes Yes
vision Yes Yes
streaming Yes Yes
realtime web No Yes

Benchmark comparison

Higher is better for all benchmarks shown.

BenchmarkCategoryGPT-4o MiniGrok 3Δ
GPQA Diamond reasoning 84.6
AIME 2025 math 93.3

Per-call cost on typical workloads

Workload (in/out tokens)GPT-4o MiniGrok 3Cheaper by
Standard chat (1K / 500) $0.000450 $0.010500 GPT-4o Mini by $0.010050
RAG (4K / 500) $0.000900 $0.019500 GPT-4o Mini by $0.018600
Long doc (20K / 1K) $0.003600 $0.075000 GPT-4o Mini by $0.071400
Very long context (100K / 2K) $0.015900 $0.322500 GPT-4o Mini by $0.306600

When to choose GPT-4o Mini over Grok 3

  • Per-token input cost is 95% lower — meaningful for high-volume workloads.

When to choose Grok 3 over GPT-4o Mini

  • Larger context window (1.0M vs 128K).
  • Supports realtime web — GPT-4o Mini does not.

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