Compare/Grok 4 Fast (Reasoning) vs Hy3

Grok 4 Fast (Reasoning)vsHy3

Side-by-side comparison of pricing, 12 benchmarks, and generation speed.

SpaceXAI

Grok 4 Fast (Reasoning)

Input
$0.2/M
Output
$0.5/M
Speed
TTFT
Tencent

Hy3

Input
$0.14/M
Output
$0.55/M
Speed
67 tok/s
TTFT
2.88s

Winner by Category

Cheaper
Hy3
Faster (tok/s)
Hy3
Lower Latency
Hy3
Benchmarks (0-2)
Hy3

Pricing Comparison

MetricGrok 4 Fast (Reasoning)Hy3
Input ($/M tokens)$0.2$0.14
Output ($/M tokens)$0.5$0.55
Cost for 1M input + 100K output tokens:
Grok 4 Fast (Reasoning)$0.25
Hy3$0.20

Speed Comparison

Output Speed (tokens/s) — higher is better
Grok 4 Fast (Reasoning)
Hy3
67 tok/s
Time to First Token (seconds) — lower is better
Grok 4 Fast (Reasoning)
Hy3
2.88s

Editorial Analysis

Verdict. Hy3 takes the aggregate benchmark matchup 2–0 across 2 categories. Real workloads usually care about a handful of specific tasks — see the per-benchmark table above.

Pricing. Both models sit in the budget bracket for output-token pricing. At 0.9× the per-million-token cost, Grok 4 Fast (Reasoning) is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). Grok 4 Fast (Reasoning) makes more sense when output volume is low and absolute reasoning quality justifies the premium.

Strengths. Grok 4 Fast (Reasoning) is strongest on Intelligence Index (27.9). Hy3 leads on Coding Index (58.8), Intelligence Index (42.2).

Speed. Speed data is incomplete for this pair; benchmark and price should decide.

Provider. SpaceXAI and Tencent sell to overlapping but distinct developer audiences: SpaceXAI tends to ship frontier reasoning models with premium positioning, while Tencent often prices more aggressively. Your existing vendor relationships, billing, and SLA preferences may matter as much as the raw numbers above.

Workload cost. Workload scenarios (per million requests at 30M input + 15M output tokens): Grok 4 Fast (Reasoning) costs $13.50 ($162/year); Hy3 costs $12.45 ($149/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Grok 4 Fast (Reasoning) ≈ $2.00/run, Hy3 ≈ $1.80/run. At agent/realtime scale (200M input / 100M output per million requests): Grok 4 Fast (Reasoning) ≈ $90/run, Hy3 ≈ $83/run. Hy3 becomes more attractive at higher volume — the absolute per-token pricing difference compounds when you ship at scale.

Recommendation. Both models have legitimate use cases — the right answer depends on whether you are optimizing for benchmark ceiling, latency, or unit cost. Start with the cheaper / faster model, evaluate against your specific task, and only switch if the upgrade shows a meaningful lift.

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
27.942.2
Coding Index
58.8
Math Index
GPQA Diamond
MMLU-Pro
LiveCodeBench
AIME 2025
MATH-500
Humanity's Last Exam
SciCode
IFBench
TerminalBench
Grok 4 Fast (Reasoning)0 wins
2 winsHy3

Frequently Asked Questions

Which is cheaper, Grok 4 Fast (Reasoning) or Hy3?

Hy3 is cheaper overall. Its blended price (3:1 input/output ratio) is $0.24/M tokens vs $0.28/M for Grok 4 Fast (Reasoning).

Which model performs better on benchmarks?

Hy3 wins 2 out of 12 benchmarks compared to 0 for Grok 4 Fast (Reasoning). See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Hy3 generates tokens faster at 67 tok/s vs — tok/s. However, Hy3 has lower time-to-first-token (2.88s vs —s).

When should I use Grok 4 Fast (Reasoning) vs Hy3?

Choose based on your priorities: Hy3 for lower cost, Hy3 for stronger benchmark performance, and Hy3 for faster generation. For latency-sensitive apps, check the TTFT comparison above.