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Synthetic Humans

Ask anything, answers in seconds

Sunzu turns your customer data into synthetic humans your team can ask anything. Product, design and marketing teams run interviews, concept tests, usability studies and ad testing in seconds, not the weeks traditional research takes.

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See Sunzu in 30 seconds

From your data to synthetic humans you can trust. The whole idea, in half a minute.

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What is synthetic user research?

Synthetic user research means putting your questions to AI models of your customers instead of waiting weeks to recruit real ones. The models are built from your own customer data, and every answer traces back to a source.

Engineered

Built from your CRM, interviews, surveys and analytics. Tested before use. Every answer cites its source.

Prompted

An LLM asked to roleplay your customer. Fluent and agreeable, but not based on your data. That is not research.

How Sunzu synthetic humans compare with traditional research and synthetic users with LLM
Dimension Sunzu synthetic humans Traditional research Synthetic users with LLM
Time to answersSecondsWeeksSeconds
Grounded in your dataYes, built from your customer dataYes, real participantsNo, generic training data
Traceable and auditableEvery answer cited to a sourcePartial, manualNone
Cost per studyLowHigh (recruit and incentivise)Low
Scale and reachOn demand, any segmentLimited by recruitingUnlimited but ungrounded
Best used forFast, grounded first-pass researchHigh-stakes, definitive decisionsNothing you need to trust

Read the method: Engineered, not prompted and 9/10 teams make the same mistakes.

Customer-centric teams

Why Sunzu

Transform your team. With Sunzu, anyone can ask anything and get answers in seconds. From your browser, or directly from Claude, Slack or Teams.

Real fast

Turn 2 weeks of research into seconds. Launch customer interviews and concept tests, run usability and ad tests at lightning speed.

All managed by an AI moderator who designs and runs your tests, ensuring robust insights, real fast. So stop waiting and get insights.

Real research

When research is rationed, teams rely on guesswork. We build Sunzu for everyone, so anyone can ask anything at any time.

Teams become more customer-centred, and research stops being a bottleneck and starts being a habit.

Robust

Traditional panels are gamed: professional respondents hot-housed across studies, screeners cheated, and bots posing as humans. That rot is corrosive to data quality.

You already have real customer data. Sunzu turns it into synthetic humans you can rely on: research that holds up when the rot is everywhere else.

Realistic

Prompting an LLM to roleplay a user is research theatre, not research. Generic AI averages toward an agreeable, frictionless person that does not exist.

Sunzu synthetic humans are grounded in cognitive architecture and behavioural economics. They satisfice, contradict themselves, and behave like your actual users do.

From the field

Testimonials

In just a couple of months, over 170 of our colleagues have run over 500 studies.

We’re now directly integrating synthetic humans into many of our research, product and marketing workflows.

Leah Kennedy
Leah Kennedy Director, Consumer Insights & Strategy Gen, Cyber Security

In a market flooded with AI-generated noise, this was the first platform that genuinely earned our trust.

By grounding its models in research principles, behavioural science, and real customer data, it delivers insights that feel credible, transparent, and actionable.

It changed our perspective on what’s possible with AI in customer research.

Lisa Payne
Lisa Payne Director, Global Product and Design Condé Nast, Publishing
How it works

Your synthetic audience

We turn the customer data you already have into a synthetic audience your team can question in seconds.

  1. Your insight

    Bring in what you already have: CRM exports, surveys, transcripts, NPS, product analytics, support themes, churn analyses, or research repositories. Sunzu maps each segment across motivations, objections, values, and decision drivers.

  2. Our model and data

    Your audience is mapped through our cognitive architecture, covering perception, memory, attention and goal-setting, so each synthetic human reasons like the customer it is modelled on. The full science is in the section below.

  3. Embed in your workflows

    Launch a custom instance, or work straight from Claude CoWork, Anthropic's AI workspace. Run depth interviews, concept testing, UX testing and ad testing in one place. Or connect through MCP and launch depth interviews and concept tests from Claude, ChatGPT, or any tool that speaks it.

Every study type

Use cases

Everything in your research stack.

Discover

Customer interviews

Depth interviews that surface the why behind your numbers, moderated end to end.

Test

Concept test

Put rough ideas in front of your audience before a line of code is written.

Prioritise

Feature testing

Rank the roadmap by what customers would actually use, not who shouts loudest.

UX

Usability test

Walk synthetic humans through your flows and see exactly where they hesitate.

Creative

Ad testing

Pressure-test copy and creative against the segment it is meant to move.

Methods

Qualitative and quantitative

Open exploration or structured measurement, from the same synthetic audience.

Run your first exploration with us. Book a call
Built to hold up

Trust

Grounded in your data, not guesswork. Every finding traces back to evidence you already have.

Grounded in your customer data

Your synthetic humans start with your signal: customer records, research, behaviour, feedback, and business context. External enrichment supports the model, but does not replace your data.

Traceable by default

Every answer is inspectable. Researchers can review why a synthetic respondent answered a certain way and what evidence informed the output.

Designed for human validation

Sunzu helps teams decide what to validate with humans, not avoid human research. It front-loads exploration and makes recruited studies sharper.

One workspace across every study type

Run interviews, concept testing, UX testing, and ad testing inside a single audience workspace. No switching tools.

Connects to your existing stack

Sunzu connects to the tools where research work already lives: Figma, Jira, Confluence, and Miro. It speaks MCP, so studies launch from Claude or ChatGPT too. Something custom? Just ask.

The science behind Sunzu

How we model human behaviour

Synthetic humans are only as good as the science underneath them. Sunzu is built on computational frameworks from cognitive science and behavioural economics, not generative AI roleplay.

Grounded in reality.

We validate against real human behavioural data, not synthetic training sets. Our models overcome the three critical failures of current generative AI simulators: persona homogenisation, tunnel vision in isolated scenarios, and optimism bias that erases authentic friction.

The result: synthetic humans who behave like your actual users, including their frustrations, mistakes, and unexpected paths.

Cognitive Architecture

We model how people actually think, not just what they say. Our system simulates perception, memory formation, attention, and goal-setting using computational frameworks that mirror human mental processes.

This creates agents that reason like real users, with both deliberate analysis and fast intuitive judgments.

Decision Model

People don't optimise perfectly. They satisfice, rely on heuristics, and make irrational choices under pressure. Our decision model captures both rational evaluation and the computational constraints that lead humans to suboptimal decisions.

This lets synthetic humans predict not just ideal choices, but the messy, real-world decisions your actual users make.

Behavioural Model

Authentic behaviour emerges from context, history, and cross-scenario consistency. Unlike isolated response generators, our behavioural model maintains causal chains across situations.

It remembers past interactions, maintains preferences over time, and exhibits long-horizon patterns that reflect how real people navigate complex product experiences.

Primitives

Every complex human behaviour decomposes into fundamental building blocks: basic psychological constructs, elemental responses, and atomic actions.

Our primitives preserve the heterogeneity of real users: individual differences, edge cases, and long-tail behaviours that get lost when generative AI averages toward a generic positive person.

Common questions

FAQ

No. Sunzu is designed for human-in-the-loop research. It helps teams explore faster, sharpen hypotheses, and identify which questions genuinely need recruited participants. Synthetic research complements human research. It does not replace it.
Start with what you already have: CRM exports, survey data, interview transcripts, NPS, support themes, product analytics, or existing research. The more customer signal you bring, the more grounded the synthetic audience becomes.
Generic AI roleplay has no provenance and tends to produce shallow, agreeable answers. Sunzu grounds every synthetic respondent in your customer data, maps them through a structured behavioural framework, and makes every output traceable for methodological review.
Setup is measured in days, not months. You bring the customer data you already have: CRM exports, transcripts, survey results, or research repositories. Sunzu builds the synthetic audience from there. The 30-minute call is a good place to map this out against your specific context and data.
Sunzu is operated by Alpha Base OS Ltd (ICO registration C1103931). Customer data uploaded to a workspace is processed solely for the contracted research purpose. We do not use workspace data for model training or third-party advertising. Full detail is in our Privacy Policy, linked in the footer.
Sunzu benchmarks synthetic outputs against human research and established testing platforms. Current figures reflect internal back-testing: ~10% deviation in quantitative concept testing, and one Sunzu study finds 85% of what a study on thousands of real humans finds, where a professional six-person study finds 60%. Methodology is available on request.
The people behind Sunzu

Meet the team

Alex

Alex

Head of Commercial

Human-centred research and product, making synthetic audiences that enterprise teams trust and adopt.

Yoann

Yoann

Head of Product

Product strategy and engineering depth, turning hard questions into answers in seconds.

Ludo

Ludo

Head of Technology

Enterprise AI engineering, grounding synthetic humans in real behavioural data.

Bring one live research question.
Leave with a sharper study plan.

Book 30 minutes. Come with a live question your team is circling. Not a hypothetical. We will model the audience and run the first exploration together, so you leave with a clear read on whether Sunzu is right for what you are trying to do.

Book a call

We'll start with your need. 30 minutes, no deck, no commitment.