Product and UX

Free Product Experiment Design Tool.

Experiment design with success and stopping criteria.

Turn a product hypothesis into an explicit test plan and keep measurement choices tied to the decision it should inform.

Chrome extension + account required.
25 free automation tasks/month across tools. Browser-provider limits apply.

WHAT TO HAVE READY

Hypothesis, metrics and constraints.

YOUR STARTING POINT

A task you can make yours.

Copy it here. Paste it into WebAct when you are ready.

This page prepares your prompt. The task runs in WebAct.

01

Make the task yours.

Review the prompt above. Add your goal and any requirements that matter.

02

Bring it to WebAct.

Open WebAct, paste the task and provide your source material. Start in Chat for a draft or explanation; use Task when you want an approved browser action or file.

03

Check the useful part.

Use the result as an editable draft or analysis. Check it against the supplied facts and your intended audience before relying on it or sharing it.

A PRACTICAL GUIDE

How to use the Product Experiment Design Tool.

Define the hypothesis, measurement and interpretation before running an experiment. Consider what result would change the decision, not only what would confirm the idea.

Make the workflow fit your task.

State the proposed mechanism, comparison and outcome measure before launching the test. Define what would change the product decision and record practical limits on the sample, observation window and interpretation.

What you provide
Hypothesis, metrics and constraints.
What you get
Experiment design with success and stopping criteria.

See the input and the result.

Illustrative input and output · a teaching example, not a live WebAct run

Example input

Design a formative experiment for the hypothesis that previewing changed rows reduces incorrect approvals. Use comparable invoice-review tasks, current and proposed views, and record correct completion plus incorrect approvals.

Completed example

Hypothesis: the preview makes changed rows easier to identify before approval.
Comparison: current view versus proposed preview on comparable tasks.
Primary observation: incorrect approvals per review attempt.
Additional observations: correct completion and time needed to finish.
Controls: keep task difficulty and instructions comparable; vary order to reduce a simple practice effect.
Decision: investigate whether observed differences support further testing; sample size and evaluation window must be agreed before running the study.
Download this example

Load this input into the prompt, then copy it to WebAct to try the task. Your result may differ from the illustration.

Decisions and troubleshooting.

Should an experiment measure only the desired positive outcome?

Include relevant failure or guardrail measures. An improvement in one metric may come with a cost elsewhere in the user experience.

Why does a positive result fail to answer the original question?

Check whether the test changed several things or measured a proxy unrelated to the decision. Narrow the claim to what was actually observed.

Try it with your own source.

Replace the example with your material in the task prompt. Keep the requirements you need, then copy the task into WebAct.

Customize and copy the task ↑
BEFORE YOU BEGIN

Using WebAct.

The prompt and example are available here. Run your task in the WebAct Chrome extension.

Is this tool free?

You can copy and edit the prompt here for free. To use it with WebAct, install the Chrome extension, create and verify your account, and connect an available browser ChatGPT session. The Free plan includes 25 user-started automation tasks per calendar month, shared across tools. Ordinary browser Chat is separate; provider limits apply.

Learn about shared context in our privacy policy and choosing Chat or Task.

FROM A PROMPT TO YOUR OWN WORK

Bring the task to your page.

Install WebAct, add your source material and make the result yours.

Install WebAct