GPT-3.5 Turbo
Fast and lightToolsOpenAI · Released May 2023 · Knowledge cutoff September 2021
GPT-3.5 Turbo is OpenAI's fastest model. It can understand and generate natural language or code, and is optimized for chat and traditional completion tasks. Training data up to Sep 2021.
It is part of OpenAI's GPT family, where Sol, Luna and Terra mark the current generation's capability tiers and Pro servings trade speed for deeper computation.
Facts and pricing
- Provider
- OpenAI
- Context window
- 16K tokens
- Input price
- 5.5 credits / 1M tokens ($0.50 raw)
- Output price
- 16.5 credits / 1M tokens ($1.50 raw)
- Vision (image input)
- No
- Tool calling
- Yes
- Extended reasoning
- No
Credits are what Zeplik bills: 1 credit = $0.10, computed from the raw provider rate with a 1.10x margin. Raw prices shown per 1M tokens.
Try GPT-3.5 Turbo now
What GPT-3.5 Turbo is best for
- High-volume everyday tasks where speed and cost matter: summaries, drafts, quick questions
- Tool use and agents: reliably calls functions, so it can search, run skills and drive workflows
Example prompts
Prompts that suit a fast and light model like GPT-3.5 Turbo:
- Summarize this article in five bullet points
- Rewrite this email to be shorter and friendlier
- Give me ten name ideas for a hiking newsletter
- Translate this paragraph to Spanish and keep the tone
OpenAI family
| Model | Context | Input cr/M | Output cr/M | Released |
|---|---|---|---|---|
| GPT-6 Astra | 1.1M | 110 | 550 | September 2026 |
| GPT-6 Astra Pro | 1.1M | 110 | 550 | September 2026 |
| GPT-5.6 Luna Pro | 1.1M | 2.2 | 13.2 | July 2026 |
| GPT-5.6 Luna Pro (batch) | 1.1M | 1.1 | 6.6 | July 2026 |
| GPT-5.6 Luna (batch) | 1.1M | 1.1 | 6.6 | July 2026 |
| GPT-5.6 Luna | 1.1M | 2.2 | 13.2 | July 2026 |
| GPT-5.6 Terra Pro (batch) | 1.1M | 11.0 | 66.0 | July 2026 |
| GPT-5.6 Terra Pro | 1.1M | 22.0 | 132 | July 2026 |
| GPT-5.6 Terra | 1.1M | 22.0 | 132 | July 2026 |
| GPT-5.6 Terra (batch) | 1.1M | 11.0 | 66.0 | July 2026 |
Frequently asked questions
- What is GPT-3.5 Turbo?
- GPT-3.5 Turbo is an AI model by OpenAI. GPT-3.5 Turbo is OpenAI's fastest model. It can understand and generate natural language or code, and is optimized for chat and traditional completion tasks. Training data up to Sep 2021.
- How much does GPT-3.5 Turbo cost on Zeplik?
- Input tokens cost 5.5 credits per million and output tokens 16.5 credits per million (1 credit = $0.10; the raw provider rates are $0.50 and $1.50 per million). New accounts start with free credits.
- How long can a conversation with GPT-3.5 Turbo be?
- GPT-3.5 Turbo has a 16K-token context window (16,385 tokens), which covers the conversation plus any documents you attach.
- Does GPT-3.5 Turbo support images and tools?
- GPT-3.5 Turbo is text-only and supports tool calling.
Related models
GPT-6 Astra is OpenAI's flagship model for demanding end-to-end work. It is suited for advanced analysis, software engineering, deep research, scientific work, and document creation, with particular strengths in long-horizon...
GPT-6 Astra Pro is the same underlying model as [GPT-6 Astra](https://openrouter.ai/openai/gpt-6-astra), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode
GPT-5.6 Luna Pro is the same underlying model as [GPT-5.6 Luna](https://openrouter.ai/openai/gpt-5.6-luna), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode
GPT-5.6 Luna Pro is the same underlying model as [GPT-5.6 Luna](https://openrouter.ai/openai/gpt-5.6-luna), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...
More you can do with GPT-3.5 Turbo
- 465 AI skillsReady-to-run expert methods for writing, data, code and more, each running on GPT-3.5 Turbo or any model you pick.
- 997 integrationsConnect Gmail, Slack, GitHub, Notion and hundreds more so the assistant can work in your apps.
- Simple pricingPlus, Pro and Max plans with a monthly credit allowance that works across every model.