Pairwise benchmark snapshot · Aug 1, 2026
In this head-to-head showdown, GPT-4.5 Orion delivers higher overall intelligence and human-preferred responses (Elo 1,540 vs 1,295), while GPT-4.5 Orion leads in SWE-bench software engineering benchmarks (71%), 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
Previous Google speed workhorse.
OpenAI largest dense non-reasoning model with expansive world knowledge and reduced hallucinations.
Currently comparing Gemini 2.5 Flash vs GPT-4.5 Orion. Alternative family tiers available.
Δ 245 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 2.5 Flash | GPT-4.5 Orion | Advantage Delta |
|---|---|---|---|
| Preference Elo | +245 | ||
| Coding Elo | — | — | |
| LiveBench | +17.1% | ||
| SWE-bench | +23% | ||
| GPQA Diamond | +15.8% | ||
| Time to first token | +240 ms | ||
| Output speed | 185 tok/s | 60 tok/s | +125 tok/s |
| Input price | $0.1/1M | +$74.9/1M | |
| Output price | $0.4/1M | $150/1M | +$149.6/1M |
| Context window | +872k |
Simulate monthly production API costs in USD (US Dollar).
Gemini 2.5 Flash is estimated to save $4,865.50/month ($58,386/year).
Higher SWE-bench (71%).
Lower output list price ($0.4/1M).
Lower TTFT (110 ms).
Larger window (1M).
Both accept images. Defaulting to the higher-Elo side (GPT-4.5 Orion).
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | GPT-4.5 Orion | Higher SWE-bench (71%). |
| 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 2.5 Flash | Larger window (1M). |
| Screenshots / vision | GPT-4.5 Orion | Both accept images. Defaulting to the higher-Elo side (GPT-4.5 Orion). |
No comments posted on this matchup yet. Be the first to share an evaluation note!
Dynamic OpenGraph banner generated at /compare/gemini-2-5-flash-vs-gpt-4-5/opengraph-image
Verified Head-to-Head Telemetry