Gemini 2.5 Flash vs GPT-5
2026 - Pricing, benchmarks, and use case comparison
Quick take
- •Gemini 2.5 Flash is 99% cheaper on input tokens - better for high-volume workloads.
- •Gemini 2.5 Flash has a 1M context window - 8x larger than GPT-5's 128K. Better for long documents and large codebases.
Specs comparison
| Gemini 2.5 Flash | GPT-5 | |
|---|---|---|
| Provider | Google DeepMind | OpenAI |
| Type | Closed source | Closed source |
| Context window | ✓1M | 128K |
| Input / 1M tokens | ✓$0.075 | $10.00 |
| Output / 1M tokens | $0.30 | $30.00 |
| Release date | 2025-05 | 2025-06 |
Benchmarks
| Benchmark | Gemini 2.5 Flash | GPT-5 |
|---|---|---|
| MMLU | ~89% | - |
| HumanEval | ~85% | - |
Scores sourced from official provider release posts.
Strengths
Gemini 2.5 Flash
- ✓Exceptional price-to-performance ratio
- ✓1M context at near-commodity pricing
- ✓Multimodal support at low cost
- ✓Fast inference latency
- ✓Strong summarization and classification
GPT-5
- ✓Strong general-purpose reasoning
- ✓Excellent multimodal understanding
- ✓Broad domain knowledge
- ✓Consistent instruction following
- ✓Widely supported by third-party tools
Which should you choose?
Choose Gemini 2.5 Flash if you need...
- →High-volume, long-context tasks
- →Cost-sensitive production workloads
- →Document and media summarization
- →Retrieval-augmented pipelines
Choose GPT-5 if you need...
- →General-purpose API integrations
- →Multimodal applications
- →Complex reasoning tasks
- →Enterprise deployments