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Measure clicks before building

Scaled prototype testing built for AI-powered product teams.

Test prototypes built with:

Price alert button designs a/b testMulti-flow Comparison
Status
100%
345/345 responses
Completed in 1hr 56min

PrototypeAdeliveredaclearadvantageforthepricealertfeature:"Watchitforme"achieveda76%clickrate,comparedwith48%forPrototypeB’s"Pricealert."Thisdifferenceisstatisticallysignificant,providingstrongevidencethatPrototypeA’streatmentdrivesmoreengagement.SentimentalsofavorsPrototypeA,with46%positiveresponsesonclarityversus34%forPrototypeB,thoughthisdirectionalliftisnotstatisticallysignificant.

Prototypes
Prototype ATravel discovery app prototype flow
Prototype BTravel discovery app prototype B
Button click rate
Statistically significant differences
The click-rate difference is unlikely to be due to chance, supporting Prototype A as the stronger performer.

Button 1: Price alert

76%
48%
0%25%50%75%100%
User sentiment
No statistically significant differences
The sentiment results suggest a trend, but the evidence is not strong enough to conclude that the prototypes differ.

Question 1: "The purpose of the prototype is clear to me" - Positive Responses

46%
34%
0%25%50%75%100%

From ideas to decision in hours.

You are just 3 easy steps away from real quantitative UX insights.

Bring your prototype

Drop in a Figma file, a Vercel link, or a Lovable build. All interactivity stays intact.

Import prototype to preview

Define what good looks like

Pick the behaviors and perceptions that matter. We handle the sample sizing and statistical setup for you.

Pick a button from each prototype to Compare
Prototype A
Prototype B
Get robust insights

Hundreds of real users go through your prototype. You get conversion lift, drop-off points, and confidence intervals you can defend.

Recruitment Goal Helper
participants
Power Analysis

Your goal is too low to detect statistical differences.

Recruit with Flux

Iterate faster, with confidence.

Prototyping is easier than ever before, but how do you know which one to build? Flux gives you the conviction you need.

Quant UX research, demystified

User journeys insight preview
User journeys

Watch where participants go, where they hesitate, and which paths actually convert.

Button clicks insight preview
Button clicks

Compare prototype variants with measurable click-through outcomes.

User sentiment insight preview
User sentiment

Capture top-2-box agreement and confidence intervals without hand-building a report.

Think aloud insight preview
Think aloud

Pair quantitative results with the moments that explain why users behaved that way.

A vibe check is not an A/B test.

Flux is not your traditional user testing tool. It is here for the next level: which version would win, by how much, and is the difference even real?

Qualitative Research
(e.g., Maze, UserTesting, Dscout, Great Question, etc.)
Question answered
"What's confusing and why?"
"Which version should we ship?"
Sample size
5–50 users
Hundreds to thousands
Output
Recordings and themes
Lift, significance, confidence
Statistical rigor
No
Yes
Decision on
Directional insights
Measurable results
Cost calculator

$1,725+*

$518@$1.50 ea.$1,208 cheaper
* Based on estimated recruitment cost of $5.00 per participant for illustrative purposes; not actual cost on the platforms.

What we're hearing from teams

“Flux can help deal with rapid development cycles that make some of the concepts I want to explore irrelevant by the time I figure out how to test them.”

UX Researcher - Big Tech

“Great for more ambiguous testing where we want to get a quant pulse on key changes without building extensively.”

Product Manager - Consumer App

“Good tool for designers in a team that wants to democratize sound research.”

UX Researcher - Consumer App

“Flux helps when we have prototypes but no bandwidth to fully build something to test with confidence.”

UX Research Manager - Consumer App

“After doing interviews with a dozen users and identifying a promising direction, this can be a way to elevate the confidence of the insights with more tangible evidence.”

UX Researcher - Big Tech

“Being able to reduce the number of design variants before developing them further is a great advantage. It's a way of doing no-code A/B testing.”

Engineering Manager - Consumer App

Frequently asked questions

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