Updated 21 October 2026
What is synthetic user testing?
Synthetic user testing means sending simulated users, built by AI, through a website or product to see where they hesitate, what they look for and where they leave. It works before you have traffic, and a run takes minutes, not weeks. It gives you reasons to check, not a forecast of how many real people will buy.
How Barbwire does it
- Barbwire reads your site and builds five buyer personas for your market: the ideal buyer, a skeptic, a borderline fit, a skimmer and a stakeholder.
- You send one in. It walks your live site in a real browser, up to 15 steps, and says what it thinks at each step.
- Each site gets a skeptic built to say no. Leaving is a normal result.
- You get a yes or no, a replay with screenshots, and the fixes ranked worst first.
- Fix the page, then send the same persona again to see if the no turns into a yes.
- It works with zero traffic, and there is nothing to install.
- It never types into or submits a form, and it stays on your domain.
See a full run in the example report.
How it compares
Each method answers a different question. Most teams use more than one.
| Method | What it does well | What it misses |
|---|---|---|
| Heat maps and recordings (Hotjar, Clarity) | Show what real people did on your pages, at scale. | Show where people left, not what they were looking for. Need traffic first. |
| Testing with real users | Real people in their own words: the strongest evidence you can get. | Takes weeks to recruit and costs money per session, so small teams run it rarely. |
| An internal review | Fast and free, by people who know the product. | Every sentence makes sense to the people who wrote it. |
| Synthetic user testing (Barbwire) | A buyer’s reason in words, with a screenshot, in about a minute. Works before launch. Send the same buyer again after a fix. | One simulated persona is one point of view. It does not tell you how many real people will buy. |
Limits
One simulated persona is one point of view. Use a run to decide what to change, then send the same persona again to check that the change works.
Runs vary a little, so trust a flip, not a one-point move.
A persona visits public pages only. It does not sign in, and if a captcha or bot check stops it, the report says so and the run is free.
Questions
- Does synthetic user testing replace testing with real users?
- No. Real users give you real words and real numbers. Synthetic testing finds likely problems quickly, before launch or between rounds with real people, so the sessions you pay for go to the questions that are left.
- How far can I trust an AI persona?
- Treat it as one point of view. Runs vary a little, so trust a flip from no to yes, not a one-point move in how keen the persona is. Barbwire personas start doubtful, and each site gets a skeptic built to say no.
- Do I need traffic?
- No. The persona visits your site itself, so it works on a page that went live today or one that is not launched yet, as long as a stranger can open it.
- Will it fill in my forms or create fake sign-ups?
- No. A persona reads, scrolls and clicks links. It never types or submits a form, and it stays on your domain.
- What does it cost?
- Free gives you 0 runs. Pro is €49 a month for 60 runs, and Team is €149 a month for 250 runs. A run is one persona sent through your site once.