Pairwise benchmark snapshot · Aug 1, 2026
In this head-to-head showdown, Gemini 2.5 Flash delivers higher overall intelligence and human-preferred responses (Elo 1,295 vs 1,260), while Gemini 2.5 Flash leads in SWE-bench software engineering benchmarks (48%), while Gemini 2.5 Flash is more budget-friendly at $0.4/1M per 1M output tokens. Review the complete breakdown below to determine which model best fits your performance and budget requirements.
9 direct benchmark disciplines evaluated across capability, speed, and cost
First million-token Gemini Pro. Baseline for 1.5 vs 2.5 vs 3.x Pro.
Previous Google speed workhorse.
Δ 35 Arena Elo pts
185 tok/s
$0.4 / 1M output
Relative percentile scores computed across all active models in the benchmark catalog.
Comparing top Western standard models with China's leading frontier rival across 6 skill dimensions. Tap any spoke or dot to inspect.
Category wins across reasoning intelligence, generation speed, and token cost.
Preference Elo, Coding proficiency, SWE-bench & LiveBench accuracy
Generation throughput and time to first token responsiveness
Cost per million tokens and max context window length
| Benchmark | Gemini 1.5 Pro | Gemini 2.5 Flash | Advantage Delta |
|---|---|---|---|
| Preference Elo | +35 | ||
| LiveBench | +2.2% | ||
| SWE-bench | +10% | ||
| GPQA Diamond | +10.2% | ||
| Time to first token | +130 ms | ||
| Output speed | 70 tok/s | 185 tok/s | +115 tok/s |
| Input price | $1.25/1M | $0.1/1M | +$1.15/1M |
| Output price | $0.4/1M | +$4.6/1M | |
| Context window | +1M |
Simulate monthly production API costs in USD (US Dollar).
Gemini 2.5 Flash is estimated to save $109.25/month ($1,311/year).
Higher SWE-bench (48%).
Lower output list price ($0.4/1M).
Lower TTFT (110 ms).
Larger window (2M).
Both accept images. Defaulting to the higher-Elo side (Gemini 2.5 Flash).
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | Gemini 2.5 Flash | Higher SWE-bench (48%). |
| High-volume chat | Gemini 2.5 Flash | Lower output list price ($0.4/1M). |
| Voice / low-latency UI | Gemini 2.5 Flash | Lower TTFT (110 ms). |
| Long-document RAG | Gemini 1.5 Pro | Larger window (2M). |
| Screenshots / vision | Gemini 2.5 Flash | Both accept images. Defaulting to the higher-Elo side (Gemini 2.5 Flash). |
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