Comparison · Updated Aug 24, 2026

GPT-3.5 vs GPT-4

GPT-3.5 and GPT-4 are OpenAI LLMs; GPT-3.5 is a text‑only chat model, while GPT-4 adds multimodal input and stronger reasoning.

Differences

AttributeGPT-3.5GPT-4
DeveloperOpenAIOpenAI
Released2022-11-302023-03-14
Open weightsfalsefalse
Context window4096 tokens8192 tokens
Modalitytext‑onlytext and image (multimodal)
Capabilitiesinstruction following, chatreasoning, multimodal, coding
Best forgeneral chat, lightweight applicationstasks needing advanced reasoning, image understanding, or code generation

Verdict

GPT-3.5 suits users who need a straightforward, text‑only conversational agent, whereas GPT-4 is better for those requiring stronger reasoning, image understanding, or advanced coding assistance.

Analysis

Overview GPT-3.5 and GPT-4 are both large language models developed by OpenAI. They share the same developer and are closed‑weight models, meaning their parameters are not publicly available. GPT-3.5 debuted in November 2022 as the instruction‑tuned refresh that powered the original ChatGPT release. GPT-4 followed in March 2023 as a multimodal successor, expanding the model’s abilities beyond pure text.

Where they differ The most concrete differences lie in the context window and modality. GPT-3.5 provides a 4096‑token context window, while GPT-4 doubles that to 8192 tokens, allowing longer inputs or outputs. Regarding modality, GPT-3.5 is strictly text‑only, whereas GPT-4 accepts both text and image inputs, enabling visual understanding tasks. Capability-wise, GPT-3.5 is highlighted for instruction following and chat, making it well suited for standard conversational use. GPT-4 adds reasoning, multimodal understanding, and coding assistance to its repertoire, indicating stronger performance on complex problem‑solving and code generation scenarios.

Which to choose Choosing between the two depends on the intended use case. If the application requires a lightweight, cost‑effective chatbot that handles only text, GPT-3.5 remains a solid option. For projects that benefit from longer context, image processing, deeper logical reasoning, or sophisticated code generation, GPT-4 offers the additional capabilities needed to meet those demands. Both models continue to be accessible via OpenAI’s API, with selection guided by the specific trade‑offs between resource constraints and required functionality.

Frequently asked

Is GPT-4 free to use?
GPT-4 is not freely available for unrestricted use; access is provided through OpenAI’s API under usage‑based pricing or via certain product integrations. There is no fully free, open‑weight release of GPT-4. Users must comply with OpenAI’s terms and any associated costs.
Can GPT-3.5 understand images?
No, GPT-3.5 is a text‑only model and does not have image input capabilities. Its modality is limited to processing and generating textual data only. For visual understanding tasks, a multimodal model such as GPT-4 is required.
Which model has a larger context window?
GPT-4 has the larger context window at 8192 tokens, double the 4096‑token window of GPT-3.5. This allows GPT-4 to handle longer documents or conversations in a single pass.
Are the weights of either model publicly available?
Neither GPT-3.5 nor GPT-4 has publicly released weights. Both are distributed as closed‑weight models accessible only through OpenAI’s hosted services or API.
What kinds of tasks is GPT-4 better suited for compared to GPT-3.5?
GPT-4 excels at tasks that require advanced reasoning, image interpretation, or sophisticated code generation. Its expanded capabilities make it preferable for complex problem solving, multimodal inputs, and scenarios where longer contextual understanding is beneficial.

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