Compare/Gemini 2.5 Pro vs GPT-5 (high)

Gemini 2.5 ProvsGPT-5 (high)

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

Google

Gemini 2.5 Pro

Input
$1.25/M
Output
$10/M
Speed
133 tok/s
TTFT
20.46s
OpenAI

GPT-5 (high)

Input
$1.25/M
Output
$10/M
Speed
81 tok/s
TTFT
98.85s

Winner by Category

Cheaper
Tie
Faster (tok/s)
Gemini 2.5 Pro
Lower Latency
Gemini 2.5 Pro
Benchmarks (0-2)
GPT-5 (high)

Pricing Comparison

MetricGemini 2.5 ProGPT-5 (high)
Input ($/M tokens)$1.25$1.25
Output ($/M tokens)$10$10
Cost for 1M input + 100K output tokens:
Gemini 2.5 Pro$2.25
GPT-5 (high)$2.25

Speed Comparison

Output Speed (tokens/s) — higher is better
Gemini 2.5 Pro
133 tok/s
GPT-5 (high)
81 tok/s
Time to First Token (seconds) — lower is better
Gemini 2.5 Pro
20.46s
GPT-5 (high)
98.85s

Editorial Analysis

Verdict. GPT-5 (high) 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 mid-tier bracket for output-token pricing. At 1.0× the per-million-token cost, GPT-5 (high) is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). GPT-5 (high) makes more sense when output volume is low and absolute reasoning quality justifies the premium.

Strengths. Gemini 2.5 Pro is strongest on Coding Index (33.3), Intelligence Index (25.9). GPT-5 (high) leads on Coding Index (37.8), Intelligence Index (35.3).

Speed. On throughput, Gemini 2.5 Pro generates tokens at 133 tok/s versus 81 tok/s — about 40% faster. On time-to-first-token, Gemini 2.5 Pro responds in 20460ms vs 98850ms, which matters most for chat-style UIs.

Provider. Google and OpenAI sell to overlapping but distinct developer audiences: Google tends to ship frontier reasoning models with premium positioning, while OpenAI 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): Gemini 2.5 Pro costs $187.50 ($2250/year); GPT-5 (high) costs $187.50 ($2250/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Gemini 2.5 Pro ≈ $26.25/run, GPT-5 (high) ≈ $26.25/run. At agent/realtime scale (200M input / 100M output per million requests): Gemini 2.5 Pro ≈ $1250/run, GPT-5 (high) ≈ $1250/run.

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, Gemini 2.5 Pro is 1.65× faster (133 tok/s vs 81 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
25.935.3
Coding Index
33.337.8
Math Index
GPQA Diamond
MMLU-Pro
LiveCodeBench
AIME 2025
MATH-500
Humanity's Last Exam
SciCode
IFBench
TerminalBench
Gemini 2.5 Pro0 wins
2 winsGPT-5 (high)

Frequently Asked Questions

Which is cheaper, Gemini 2.5 Pro or GPT-5 (high)?

Both models have similar pricing. Check the detailed breakdown above for input vs output token costs.

Which model performs better on benchmarks?

GPT-5 (high) wins 2 out of 12 benchmarks compared to 0 for Gemini 2.5 Pro. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Gemini 2.5 Pro generates tokens faster at 133 tok/s vs 81 tok/s. Gemini 2.5 Pro also has lower time-to-first-token (20.46s vs 98.85s).

When should I use Gemini 2.5 Pro vs GPT-5 (high)?

Choose based on your priorities: both are similarly priced, GPT-5 (high) for stronger benchmark performance, and Gemini 2.5 Pro for faster generation. For latency-sensitive apps, check the TTFT comparison above.