Compare/Qwen3.5 Omni Flash vs Mercury 2

Qwen3.5 Omni FlashvsMercury 2

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

Alibaba

Qwen3.5 Omni Flash

Input
$0.1/M
Output
$0.8/M
Speed
255 tok/s
TTFT
1.84s
Inception

Mercury 2

Input
$0.25/M
Output
$0.75/M
Speed
835 tok/s
TTFT
3.93s

Winner by Category

Cheaper
Qwen3.5 Omni Flash
Faster (tok/s)
Mercury 2
Lower Latency
Qwen3.5 Omni Flash
Benchmarks (0-2)
Mercury 2

Pricing Comparison

MetricQwen3.5 Omni FlashMercury 2
Input ($/M tokens)$0.1$0.25
Output ($/M tokens)$0.8$0.75
Cost for 1M input + 100K output tokens:
Qwen3.5 Omni Flash$0.18
Mercury 2$0.33

Speed Comparison

Output Speed (tokens/s) — higher is better
Qwen3.5 Omni Flash
255 tok/s
Mercury 2
835 tok/s
Time to First Token (seconds) — lower is better
Qwen3.5 Omni Flash
1.84s
Mercury 2
3.93s

Editorial Analysis

Verdict. Mercury 2 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 1.1× the per-million-token cost, Mercury 2 is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). Mercury 2 makes more sense when output volume is low and absolute reasoning quality justifies the premium.

Strengths. Qwen3.5 Omni Flash is strongest on Intelligence Index (19.2). Mercury 2 leads on Coding Index (31.1), Intelligence Index (21.9).

Speed. On throughput, Mercury 2 generates tokens at 835 tok/s versus 255 tok/s — about 70% faster. On time-to-first-token, Qwen3.5 Omni Flash responds in 1840ms vs 3930ms, which matters most for chat-style UIs.

Provider. Alibaba and Inception sell to overlapping but distinct developer audiences: Alibaba tends to ship frontier reasoning models with premium positioning, while Inception 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): Qwen3.5 Omni Flash costs $15.00 ($180/year); Mercury 2 costs $18.75 ($225/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Qwen3.5 Omni Flash ≈ $2.10/run, Mercury 2 ≈ $2.75/run. At agent/realtime scale (200M input / 100M output per million requests): Qwen3.5 Omni Flash ≈ $100/run, Mercury 2 ≈ $125/run. Qwen3.5 Omni Flash 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.

Head-to-head deltas

  • On throughput, Mercury 2 is 3.28× faster (835 tok/s vs 255 tok/s). For streaming chat or real-time agents this alone often flips the recommendation.

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
19.221.9
Coding Index
31.1
Math Index
GPQA Diamond
MMLU-Pro
LiveCodeBench
AIME 2025
MATH-500
Humanity's Last Exam
SciCode
IFBench
TerminalBench
Qwen3.5 Omni Flash0 wins
2 winsMercury 2

Frequently Asked Questions

Which is cheaper, Qwen3.5 Omni Flash or Mercury 2?

Qwen3.5 Omni Flash is cheaper overall. Its blended price (3:1 input/output ratio) is $0.28/M tokens vs $0.38/M for Mercury 2.

Which model performs better on benchmarks?

Mercury 2 wins 2 out of 12 benchmarks compared to 0 for Qwen3.5 Omni Flash. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Mercury 2 generates tokens faster at 835 tok/s vs 255 tok/s. Qwen3.5 Omni Flash also has lower time-to-first-token (1.84s vs 3.93s).

When should I use Qwen3.5 Omni Flash vs Mercury 2?

Choose based on your priorities: Qwen3.5 Omni Flash for lower cost, Mercury 2 for stronger benchmark performance, and Mercury 2 for faster generation. For latency-sensitive apps, check the TTFT comparison above.