GPT-5.1 o1 vs GPT-5.4
A comprehensive 2026 comparison to help you choose the right AI tool for your needs. We tested both extensively.
Quick Verdict: GPT-5.1 o1 vs GPT-5.4
After extensive testing, **GPT-5.4 Thinking** comes out ahead with a 5.0/5 rating. It's the better choice for most users, especially those focused on Complex reasoning, agentic coding, long-document analysis, multi-step workflows. However, GPT-5.1 Thinking remains competitive and may be preferable if you prioritize Complex reasoning, math proofs, scientific analysis.
GPT-5.4 Thinking edges out GPT-5.1 Thinking with superior overall performance and features that make it the better choice for most users in 2026. With a 5.0/5 rating, it excels particularly in Complex reasoning, agentic coding, long-document analysis, multi-step workflows.
Try GPT-5.4 FreeFeature Comparison Table
Side-by-side comparison of key features and capabilities
When to Use GPT-5.1 o1 vs GPT-5.4
Choose GPT-5.1 o1 When You Need:
- Complex reasoning, math proofs, scientific analysis
Choose GPT-5.4 When You Need:
- Complex reasoning, agentic coding, long-document analysis, multi-step workflows
- Superior coding assistance and code generation
- Better quality content writing and creative tasks
- Faster response times for time-sensitive work
- Processing longer documents with 1000K context
In-Depth Analysis: GPT-5.1 o1 vs GPT-5.4
Performance & Capabilities
In our comprehensive testing for 2026, we evaluated both GPT-5.1 Thinking and GPT-5.4 Thinking across multiple dimensions including coding tasks, creative writing, reasoning problems, and general conversation quality. GPT-5.4 Thinking emerged as our top pick with an overall rating of 5.0/5.
GPT-5.1 Thinking scored 4.6/5 on coding tasks, making it an excellent choice for developers. In comparison, GPT-5.4 Thinking achieved 4.8/5 in this category.
Pricing & Value
When it comes to pricing, both require paid subscriptions. For paid plans, GPT-5.4 Thinking is more affordable at $200/month compared to $200/month.
Use Cases & Target Audience
GPT-5.1 Thinking is particularly well-suited for Complex reasoning, math proofs, scientific analysis. Its strengths make it ideal for professionals who need advanced coding help, quality content creation, and reliable AI assistance.
GPT-5.4 Thinking, on the other hand, excels at Complex reasoning, agentic coding, long-document analysis, multi-step workflows. Users who prioritize complex reasoning, will find it particularly valuable.
GPT-5.1 Thinking Pros & Cons
Pros
- Best for complex reasoning tasks
- Dynamic thinking time optimization
- Excellent for math and logic
- Great for research and analysis
Cons
- Expensive
- Slower on simple tasks
- Requires Pro subscription
- Writing can feel robotic
GPT-5.4 Thinking Pros & Cons
Pros
- 1M token context window — largest from OpenAI
- 33% fewer false claims vs GPT-5.2
- Built-in computer-use capabilities
- Intervene mid-response during reasoning
- 6x cheaper input tokens than GPT-5.2 Thinking
- Excellent for coding, agentic workflows, and document analysis
Cons
- Requires Pro subscription ($200/mo) for full access
- Slower than non-thinking variants
- Can be overkill for simple tasks
- Writing still not as natural as Claude
Best For: GPT-5.1 o1
Complex reasoning, math proofs, scientific analysis
Best For: GPT-5.4
Complex reasoning, agentic coding, long-document analysis, multi-step workflows
Frequently Asked Questions
Common questions about GPT-5.1 o1 vs GPT-5.4
Is GPT-5.1 Thinking better than GPT-5.4 Thinking in 2026?
Based on our benchmarks and analysis, GPT-5.4 Thinking performs better overall with a rating of 5.0/5. However, the best choice depends on your specific needs - GPT-5.1 Thinking excels at Complex reasoning, math proofs, scientific analysis, while GPT-5.4 Thinking is better for Complex reasoning, agentic coding, long-document analysis, multi-step workflows.
What is the price difference between GPT-5.1 o1 and GPT-5.4?
GPT-5.1 Thinking costs $200/month for paid plans. GPT-5.4 Thinking costs $200/month for paid plans.
Which is better for coding: GPT-5.1 o1 or GPT-5.4?
For coding tasks, GPT-5.4 Thinking scores higher with a 4.8/5 coding rating compared to 4.6/5.
Can I use GPT-5.1 o1 and GPT-5.4 for free?
GPT-5.1 Thinking requires a paid subscription. GPT-5.4 Thinking requires a paid subscription. Both tools offer trial periods or limited free access for new users.
Which AI has a larger context window: GPT-5.1 o1 or GPT-5.4?
GPT-5.4 Thinking has a larger context window at 1,000,000 tokens, compared to 128,000 tokens. Larger context windows allow processing more text in a single conversation.
Is GPT-5.1 o1 faster than GPT-5.4?
In our speed tests, GPT-5.4 Thinking is faster with a speed rating of 3.9/5. Response times can vary based on server load and query complexity.
Which is better for writing content: GPT-5.1 o1 or GPT-5.4?
For content writing, GPT-5.4 Thinking excels with a writing rating of 4.6/5 versus 4.4/5. Consider your specific writing needs when choosing.
Do GPT-5.1 o1 and GPT-5.4 support image generation?
GPT-5.1 Thinking supports image understanding and analysis. GPT-5.4 Thinking supports image understanding and analysis. For dedicated image generation, consider specialized tools like DALL-E or Midjourney.
Which AI should beginners choose: GPT-5.1 o1 or GPT-5.4?
For beginners, we recommend trying both during their trial periods. GPT-5.4 Thinking has a slightly better overall user experience based on our testing.
Can I switch from GPT-5.1 o1 to GPT-5.4 easily?
Yes, switching between AI tools is straightforward since they use similar prompting interfaces. Your conversation history won't transfer, but you can export important outputs. Many professionals use both tools depending on the task - GPT-5.1 Thinking for Complex reasoning, math proofs, scientific analysis and GPT-5.4 Thinking for Complex reasoning, agentic coding, long-document analysis, multi-step workflows.
Related Comparisons
Explore more AI tool comparisons
Explore More
Ready to Get Started?
Both tools offer free tiers or trials. Try them out and see which one works best for your workflow in 2026.