o1 vs GPT-3.5 Turbo
Compare pricing, context windows, and strengths for o1 by OpenAI and GPT-3.5 Turbo by OpenAI - and see how to put either to work in Appaca.
o1
A full-size o-series reasoning model trained with RL to think before answering, producing strong multi-step reasoning across math, code, and analysis tasks.
View o1GPT-3.5 Turbo
Legacy lightweight GPT model for cheap text generation and chat tasks; now replaced by faster, smarter, and cheaper 4o-mini models.
View GPT-3.5 Turboo1 vs GPT-3.5 Turbo at a glance
Specs and pricing side by side, from the Appaca AI models directory.
| Spec | o1 | GPT-3.5 Turbo |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Model type | Text | Text |
| Context window | 200K tokens | 16.4K tokens |
| Input price | $15 / 1M tokens | $0.5 / 1M tokens |
| Output price | $60 / 1M tokens | $1.5 / 1M tokens |
| Status | Current | Current |
How o1 and GPT-3.5 Turbo differ
What the numbers mean in practice when choosing between o1 and GPT-3.5 Turbo.
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GPT-3.5 Turbo is 97% cheaper on input tokens ($0.5 vs $15 per million), which adds up quickly in document-heavy workloads.
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GPT-3.5 Turbo is 98% cheaper on output tokens ($1.5 vs $60 per million) - the bigger factor for tools that generate long documents.
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o1's 200K tokens context window is roughly 12.2x larger than GPT-3.5 Turbo's 16.4K tokens, so it can work across bigger codebases, contracts, or archives in one pass.
Strengths side by side
Where each model shines, according to benchmarks and provider positioning.
o1
1. Full-scale reasoning model
- Uses reinforcement learning to generate long internal chains of thought.
- Suitable for tasks requiring deep logic, multi-step planning, and rich analytical reasoning.
2. Strong performance across domains
- Excellent at math, science, coding, and structured analytical work.
- Handles multi-step workflows and complex problem-solving with high consistency.
3. High output capacity (100K tokens)
- Enables long, detailed explanations, large documents, and multi-part analyses.
4. Image-understanding capable
- Accepts text + image inputs for visual reasoning and mixed-modality tasks.
- Output is text only, optimized for clear explanations.
5. Advanced API compatibility
- Works with Chat Completions, Responses, Realtime, Assistants, and more.
- Supports streaming, function calling, and structured outputs.
6. Stable long-context performance
- 200K-token context window supports large files, multi-document analysis, and extended conversations.
7. Designed for correctness-oriented workloads
- Prioritizes rigorous reasoning over speed.
- Useful in auditing, verification, scientific thinking, policy analysis, and legal-style reasoning.
8. Powerful but expensive
- High token costs make it suitable for selective, mission-critical reasoning rather than high-volume usage.
GPT-3.5 Turbo
1. Extremely low-cost text model
- One of the cheapest legacy models available.
- Suitable for very high-volume workloads with simple requirements.
2. Good for lightweight NLP tasks
- Classification, summarization, rewriting, paraphrasing, intent detection.
- Works for simple logic tasks and short reasoning sequences.
3. Works well for basic chatbots
- Optimized for Chat Completions API, originally powering early ChatGPT use cases.
- Good for rule-based or templated conversation flows.
4. Stable and predictable outputs
- Legacy behavior makes it suitable for systems built years ago that rely on its quirks.
- Good for backward compatibility or long-term enterprise pipelines.
5. Supports fine-tuning
- Useful for teams maintaining older fine-tuned GPT-3.5 models.
- Allows domain-specific compression of older datasets.
6. Limited capabilities compared to newer models
- No vision, no audio, no streaming, and no function calling.
- Much weaker reasoning and correctness vs GPT-4o mini or GPT-5.1.
7. Small context window (16K)
- Limited for multi-document tasks or long conversations.
- Best used for short, simple prompts or structured tasks.
8. Recommended migration path
- OpenAI explicitly recommends using GPT-4o mini instead.
- 4o mini is cheaper, smarter, faster, multimodal, and far more capable.
Use o1 or GPT-3.5 Turbo - or both
Appaca is the AI workspace for operators. Build internal tools and AI co-workers powered by o1 or GPT-3.5 Turbo - connected to your real data and ready for your whole team. No code, no deployment.
Describe it, and it's built
Tell the Appaca agent the internal tool you need and it builds a working app powered by o1 or GPT-3.5 Turbo. No code, no API keys, no deployment.
Switch models without rebuilding
Start on o1, test the same tool on GPT-3.5 Turbo, and keep whichever performs better - the rest of your app stays exactly as it is.
Automated for the whole team
Schedule tools to run on autopilot - daily digests, weekly reports, real-time triggers - and share them with your whole team from one workspace.
Describe it, and it's built
Tell the Appaca agent what your team needs and it builds a working app powered by o1 or GPT-3.5 Turbo - connected to the tools you already use.
Related comparisons
See how o1 and GPT-3.5 Turbo stack up against other models in the directory.
FAQs
GPT-3.5 Turbo is generally cheaper: $0.5 input / $1.5 output per million tokens, versus $15 / $60 for o1. Actual cost depends on how many tokens your workload reads and writes.
o1 has the larger context window at 200K tokens, compared to 16.4K tokens for GPT-3.5 Turbo. A larger window means the model can consider more text at once - useful for long contracts, codebases, or months of records.
It depends on the job. Compare the pricing, context window, and strengths above against your workload - and remember the choice isn't permanent. In Appaca you can build a tool on o1, test the same tool on GPT-3.5 Turbo, and switch at any time without rebuilding anything.
Yes. Appaca is a no-code AI workspace: describe the internal tool your team needs and the Appaca agent builds it as a working app powered by o1, GPT-3.5 Turbo, or any other model in the directory - with a built-in database, team access, and integrations. No API keys to wire up and nothing to deploy.
Build AI tools with o1 or GPT-3.5 Turbo
Describe the tool your team needs and get a working app powered by the model you choose - with a built-in database, team access, and integrations. No code, no deployment.