Pairwise benchmark snapshot · Aug 1, 2026
In this head-to-head showdown, OpenAI o1 delivers higher overall intelligence and human-preferred responses (Elo 1,512 vs 1,295), while OpenAI o1 leads in SWE-bench software engineering benchmarks (48.9%), 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 pioneer reasoning foundation model designed for complex science, math, and multi-step reasoning.
Currently comparing Gemini 2.5 Flash vs OpenAI o1. Alternative family tiers available.
Simulate accuracy gains vs added response time & token cost
Reasoning models “think before answering” by generating internal reasoning tokens. Higher effort improves math, coding, and logic accuracy, but increases response delay and token costs.
Δ 217 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 | OpenAI o1 | Advantage Delta |
|---|---|---|---|
| Preference Elo | +217 | ||
| Coding Elo | — | — | |
| LiveBench | +14% | ||
| SWE-bench | +0.9% | ||
| GPQA Diamond | +9.8% | ||
| Time to first token | +310 ms | ||
| Output speed | 185 tok/s | 45 tok/s | +140 tok/s |
| Input price | $0.1/1M | +$14.9/1M | |
| Output price | $0.4/1M | +$59.6/1M | |
| Context window | +800k |
Simulate monthly production API costs in USD (US Dollar).
Gemini 2.5 Flash is estimated to save $1,415.50/month ($16,986/year).
Higher SWE-bench (48.9%).
Lower output list price ($0.4/1M).
Lower TTFT (110 ms).
Larger window (1M).
Both accept images. Defaulting to the higher-Elo side (OpenAI o1).
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | OpenAI o1 | Higher SWE-bench (48.9%). |
| 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 | OpenAI o1 | Both accept images. Defaulting to the higher-Elo side (OpenAI o1). |
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