U.S. NEWS MONEY · MORTGAGE CALCULATOR

The 6.4%

Problem

Reframing a mortgage calculator into a 30-second guided estimate experience.

Simon Dai - Portfolio Case Study

BASELINE

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Next-Action Rate

+0%

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Why the Calculator Mattered

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This was an ad-supported fintech funnel: when users reached a useful estimate, they were more likely to compare rates, view lender offers, and take a monetizable next action.

Design clarity directly affected business conversion.

USER

Get a useful mortgage estimate in 30 seconds without requiring financial expertise.

Fast

Simple

Confident

The Original Calculator Experience

The original calculator was functional, but it asked users to complete a dense form before they could see a useful estimate.

Users had to invest effort before understanding the value.

Where users dropped off

I paired product analytics with the original experience to understand where friction appeared in the journey.

46%

Started entering info

21%

Completed required fields

18%

Reached result screen

6.4%

Took next action

The first fix wasn’t enough

After early user interviews and usability tests, we decided to add more guidance around confusing mortgage inputs. The hypothesis was simple: if users understood the fields better, more of them would complete the calculator.

Why this decision

Users were hesitating around unfamiliar terms and exact financial inputs, so the first fix focused on reducing confusion through tooltips and clearer visual explanations.

Result 

The improvement was small. Tooltips helped users who were already committed, but they did not reduce the larger barrier of time, effort, and trust before users started.

46% → 48%

Started calculator

+2 pts

21%→ 23%

Completed inputs

+2 pts

18%  → 20%

Reached result screen

+2 pts

6.4% → 6.8%

Took next action

+0.4 pts

The Real Barrier Was Time + Trust

Users didn’t need more education.
They needed a faster, lower-risk path to a useful estimate.
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0%

Expected estimate within 30 sec

0%

Hesitated at income / debt fields

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0%

Skipped Tooltips Education was too slow

0%

Raised AI privacy concerns

The problem wasn’t comprehension. It was the cost of getting started.

Time · Trust · Effort

0%

Raised AI privacy concerns

“This team fundamentally improved the way we run our operations. Onboarding now takes half the time, and the customer response has been incredible.”
Aiden Brooks

COO, Nexora Labs

0%

Raised AI privacy concerns

“This collaboration reshaped how we work internally. Our onboarding process is twice as fast, and customer reactions have been overwhelmingly positive.”
Ethan Ward

Founder & CEO


From Research Signal to Team Strategy

After research, I aligned Product, Design, Engineering, and leadership around one focused strategy: keep the calculator logic intact, redesign the intake layer, and measure success by result-screen reach and next-action rate.

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Scope

Keep calculator logic intact instead of rebuilding the core engine.

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Product

Redesign the intake layer where users start, answer, and commit.

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Trust

Make AI assistance transparent, editable, and low-risk.

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Metric

Measure result-screen reach and next-action rate, not visual polish.


The chatbox was right — and wrong
What if AI asked the questions?

Prototype signals (12 tests + 8 interviews)

Preferred guided help

75%

Understood assistant

83%

Comfortable sharing exact income / debt

33%

Wanted review / edit

92%

Raised privacy concerns

50%

Design direction

Keep the guidance. Structure the input.

AI could guide the experience, but sensitive financial inputs needed to stay structured, visible, and editable.

Map the journey first

Design implication

AI should guide the journey, not own the conversation. The right pattern was a structured flow where guidance, input, and control happened at the right moments.

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DECISIONS THAT CHANGED THE PRODUCT

We created a guided entry point that helped users estimate faster, understand assumptions, and stay in control before calculating.

DECISIONS THAT CHANGED THE PRODUCT

The final solution came from four product decisions: where AI should appear, how much information users should provide upfront, how much control they needed, and what we could ship without rebuilding the core calculator.

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Kill the Chatbox

Users liked guidance, but 50% raised privacy concerns. We kept the intelligence and removed the conversational interface.

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Use Ranges First

Exact income and debt fields made users hesitate. Range-based questions made the first step feel easier and safer.

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Show Editable Assumptions

AI could suggest defaults, but users needed to review and edit before trusting the estimate.

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Keep the Core Calculator

We redesigned the intake layer without rebuilding the calculation engine, which made the solution faster to ship.

From 6.4% to 13.8%

The final Guided Quick Fill prototype gave users a lighter way to start, review assumptions, and reach a useful estimate before taking the next step.

Final prototype

46% → 48%

Started calculator

+2 pts

21%→ 23%

Completed inputs

+2 pts

18%  → 20%

Reached result screen

+2 pts

6.4% → 6.8%

Took next action

+0.4 pts


AI Is a Complexity Decision

Connect the System

The strongest design decisions came from treating user confidence, product completion, and business conversion as one connected system.

Make AI Feel Invisible

The best AI pattern was not a visible assistant. It was guidance embedded into the workflow, reducing effort without creating new trust concerns.

Kill the Wrong Idea

The chatbox had signal, but the data showed it was the wrong interface. I kept the user need and changed the solution.

Why Tomo

Tomo is solving the same kind of problem this project taught me to care about: helping people make high-stakes financial decisions with more clarity, speed, and confidence.

I would bring a product design approach that connects user trust, AI-assisted workflows, and business outcomes — especially in the first-estimate moments where confidence either builds or breaks.