Why Does Claude Take Longer Than ChatGPT on Some Tasks?

Claude does take longer than ChatGPT on some tasks, but not on others. The difference is not simply that one model is faster than the other. It depends on the task type, whether extended thinking is enabled, and how long the response needs to be.

If you switch between assistants regularly, a tool like fenbs keeps your brief portable so you can test both on the same task and record which setup works better for the work you actually do.

The main reasons Claude can feel slower

There are three common reasons Claude takes longer on a given request: extended thinking mode is active, the response length is longer by default, or the task involves complex reasoning that Claude takes more time to process. These are different situations with different fixes.

• Extended thinking: when enabled, Claude works through a reasoning chain before answering. This adds seconds to minutes depending on the complexity. It makes harder problems more accurate but simple questions noticeably slower.
• Response length: Claude tends to write more complete, structured answers by default. A longer response takes longer to generate and longer to stream to your screen.
• Task complexity: for multi-step reasoning tasks, Claude may take more time even without extended thinking enabled, because it is generating a more thorough answer.
• Server load: like any AI service, response time varies by time of day and plan tier.

What extended thinking does to response time

Extended thinking is Claude's reasoning mode. When you ask a question and Claude works through a chain of reasoning before answering, you see a "thinking" step before the response. That step can take a few seconds for a simple problem or a minute or more for a hard one.

ChatGPT has reasoning models (the o-series) that work similarly: they take extra time before responding in order to handle harder problems more accurately. The o-series models are not the default in ChatGPT; GPT-4o is. If you are comparing response speed and you have extended thinking active in Claude but are using GPT-4o in ChatGPT, you are comparing different configurations, not different models at the same setting.

For everyday tasks where you do not need extended reasoning, turn extended thinking off. Claude without extended thinking responds more quickly, and the quality difference on simple tasks is usually small.

Response length and streaming

Both assistants stream their responses: you see text arrive token by token rather than waiting for the whole response to appear. The speed of that stream is similar between them. What differs is how much text they produce.

Claude tends to give longer, more structured answers by default. A question that ChatGPT answers in two sentences may get five paragraphs from Claude. The time to complete the response is longer, but neither assistant is "slow" in the sense of generating tokens more slowly. Claude is generating more of them.

If you want shorter responses from Claude, ask explicitly: "Answer in two sentences" or "Give a brief answer." Claude follows length instructions reliably, and the shorter response will appear faster.

When ChatGPT appears faster

ChatGPT with GPT-4o is fast on short responses. For quick lookups, brief code snippets, or yes/no answers with a short explanation, it often feels noticeably faster than Claude because GPT-4o is tuned for speed and the default response length is shorter.

For tasks where both assistants produce responses of similar length, the difference in perceived speed is smaller. For reasoning-heavy tasks where you use ChatGPT's o-series models, ChatGPT will also be slower than its default.

When Claude appears faster

Claude Haiku, the lightweight model in the Claude family, is designed for speed and cost efficiency. If you are doing tasks that do not require Claude's strongest reasoning, Haiku gives you Claude-quality instruction-following at a faster response time. Compare it to GPT-4o mini on the same tasks to find the right lightweight option for your work.

For long-document analysis, Claude's larger context window means it can process the full document in one pass rather than chunking it, which can make the total workflow faster even if the individual response takes longer.

How to measure this for your own work

The most useful measure is total time to a usable result for the task you actually care about. That includes the time to write the prompt, the wait for the response, and the time to review and use it.

A faster response that requires several follow-up corrections is slower in practice than a slower first response that gets it right. Test the full cycle, not just the first response time.

For more on choosing between ChatGPT and Claude, see Claude vs. ChatGPT. If you are comparing their project and memory features, Claude Projects vs. ChatGPT Projects covers that in detail.

How to do this with fenbs

1. Create a free account and add the project you want to evaluate speed on.
2. Write the evaluation brief: the task, the acceptable response length, and the quality criteria. Record it as the project context.
3. Connect Claude and other supported apps from Integrations. Run the same prompt in both with the same settings (both with reasoning off, or both with it on).
4. Record the result in a context note: which produced a usable result faster and why.
5. If you find different assistants suit different task types, record that as a Decision so the next session starts from the right tool choice.