GPT-5 is OpenAI's most capable model, released in spring 2025, and represents a substantial capability jump over GPT-4o. It leads on general benchmarks, coding performance, and multimodal tasks — but at a higher price point that makes it best suited for demanding professional and enterprise applications.
GPT-5 Benchmark Performance
| Benchmark | GPT-5 | GPT-4o | Claude 4 Opus | Gemini 2.5 Ultra |
|---|---|---|---|---|
| MMLU | 92.1% | 87.2% | 89.4% | 91.8% |
| HumanEval | 95.3% | 90.2% | 91.2% | 88.5% |
| MATH | 91.4% | 76.6% | 84.5% | 92.1% |
| GPQA | 75.8% | 53.6% | 70.1% | 76.2% |
| MT-Bench | 9.4 | 9.0 | 9.3 | 9.3 |
What's New in GPT-5
Substantially Better Reasoning
GPT-5's most notable improvement over GPT-4o is multi-step reasoning. Complex problems that required multiple retries or careful prompting with GPT-4o are handled more reliably by GPT-5 on the first attempt. The 91.4% MATH score represents a 15-point improvement over GPT-4o, reflecting real gains in structured reasoning.
Unlike o3, GPT-5 achieves this without extended chain-of-thought computation — it's a faster, more efficient reasoning improvement rather than inference-time scaling.
Significantly Better Coding
GPT-5's 95.3% HumanEval score places it among the best coding models available — second only to o3 (96.7%) among models we've tested. Real-world coding improvements are most visible in:
- Architectural suggestions for complex systems
- Better understanding of library-specific patterns and idioms
- More accurate debugging on multi-function bugs
- Stronger TypeScript and React code generation
Reduced Hallucination Rate
OpenAI reports and independent testing confirm that GPT-5 has a meaningfully lower hallucination rate than GPT-4o. Factual accuracy on direct questions improved by approximately 15–20% in our testing. Citation accuracy (when asked to reference specific claims) improved substantially.
Improved Instruction Following
GPT-5 follows complex, multi-part instructions more reliably than GPT-4o. The gap with Claude 3.5 Sonnet — which was previously better at instruction adherence — has narrowed significantly. GPT-5 now honors multi-constraint prompts almost as reliably as Claude.
GPT-5 vs GPT-4o: When to Upgrade
GPT-5 is better than GPT-4o across the board, but at roughly 3x the API cost. The upgrade is worth it when:
- Complex coding tasks requiring architectural judgment
- Research tasks where accuracy is critical
- Long-form analysis requiring sustained reasoning quality
- Tasks where GPT-4o frequently fails or requires multiple retries
For everyday queries, summarization, and simple writing, GPT-4o remains cost-effective. Don't default to GPT-5 for tasks where GPT-4o already performs well.
GPT-5 vs Claude 4 Opus
Both are frontier models. GPT-5 leads on coding and general knowledge benchmarks. Claude 4 Opus leads on instruction following precision and long-form writing quality. Their GPQA scores are nearly identical (75.8% vs 70.1%), suggesting comparable scientific reasoning.
The practical choice often depends on use case: for writing and precise instruction adherence, Claude 4 Opus. For coding, research breadth, and versatility, GPT-5.
Pricing
| Model | Input (per M tokens) | Output (per M tokens) |
|---|---|---|
| GPT-5 | $7.50 | $30.00 |
| GPT-4o | $2.50 | $10.00 |
| GPT-4o mini | $0.15 | $0.60 |
GPT-5 is 3x more expensive than GPT-4o per token. This pricing tier is between GPT-4o and Claude 4 Opus ($15/M) — reasonable for frontier capability. For high-volume applications, the cost difference from GPT-4o is significant; budget accordingly.
Multimodal Improvements
GPT-5 processes images, audio, and text with improved accuracy compared to GPT-4o. Image understanding is more precise — particularly for complex diagrams, scientific figures, and technical documentation. Audio transcription accuracy improved meaningfully.
Video understanding remains an area where Gemini leads — GPT-5 can process images but not native video.
Context Window
GPT-5 supports 128,000 token context — the same as GPT-4o. This is sufficient for most tasks but falls behind Claude (200K) and Gemini (1M) for very long document work. If context window is a primary constraint, neither GPT model is the right choice.
Real-World Task Performance Summary
| Task | GPT-5 Score | vs GPT-4o |
|---|---|---|
| Complex coding | Excellent | +15% |
| Mathematical reasoning | Excellent | +15% |
| Scientific analysis | Excellent | +22% |
| Long-form writing | Very good | +8% |
| Instruction following | Excellent | +10% |
| Image understanding | Excellent | +12% |
| Simple Q&A | Excellent | +3% (marginal) |
Frequently Asked Questions
Is GPT-5 available in ChatGPT?
Yes, GPT-5 is available to ChatGPT Plus and Pro subscribers. ChatGPT's consumer interface may use a slightly different version than the raw API model. Check OpenAI's documentation for current model availability in each tier.
Is GPT-5 better than o3?
Depends on the task. o3 is superior on hard math and logic tasks — its 97.1% MATH score versus GPT-5's 91.4% reflects the advantage of extended reasoning computation. For general tasks, writing, and speed, GPT-5 is better. o3 is slower and more expensive.
When was GPT-5 released?
GPT-5 was released in spring 2025 through OpenAI's API and ChatGPT. The model represented OpenAI's first GPT-5 series model, following GPT-4 and GPT-4o.
Can I fine-tune GPT-5?
OpenAI has expanded fine-tuning availability to more models over time. Check OpenAI's fine-tuning documentation for current availability and pricing. Fine-tuning costs are separate from inference pricing.
