dynamic payment calculator
May-June 2025 & January-April 2026
Optimizing a space-efficient mini calculator to drive financial transparency and boost customer interactions by 165%
project CONTEXT
Our payment calculator has received dealer feedback that it was taking up too much room on their vehicle details page. As a result, some dealers would toggle off this feature even though it helped carbuyers personalize their financing. Our goal was to reduce the calculator's real estate and support customers with robust capabilities to give them a better understanding of what they can afford.
There are two variants of the calculator: Estimates and Pre-qualified. The default calculator is the Estimates Calculator where carbuyers get estimated rates and numbers to understand if they could afford the car. The Pre-qualified Calculator automatically takes over when the customer goes through a Capital One Pre-qualification form for an auto loan. This calculator provides more penny-perfect numbers to give the customer a realistic view of their payments and rates.
My role
Design Subject Matter Expert and Lead for the Tier 1 Calculator; owned design strategy, component architecture, and evaluative research end-to-end.
Snapshot
Product Strategy & UX · Evaluative research, design systems, A/B testing · 165% ↑ engagement · 9.41% ↑ conversion
Discover
When I was on this team the first time in May 2025, I noticed there was no competitive analysis, so I created it in Lucidspark. I pulled in calculator flows from our top dealer competitors, OEMs, and non-auto calculators/financing tools. I joined at the tail end of dealer research as a note-taker for Zoom sessions. The team recently concluded UserTesting sessions with car buyers but hasn't synthesized it yet. I synthesized the 10 total customer sessions within days to keep the product manager unblocked and to learn how customers perceived the calculator concepts that were created before I joined.
I rejoined the team a year later; the designs were untouched and not pushed to market yet. It gave me time to get reacquainted with the product and understand what our new product goals were. A month later, leadership introduced a new three-tier product strategy. We pivoted the existing work to fit the newly determined capabilities. I conducted a new round of dealer research specifically on how certain capabilities — offers, incentives, taxes/tags/title fees, zip code — should be surfaced.
Define
Ran hands-on hot houses (paper prototypes, whiteboarding) to define what the calculator's capabilities look like at each tier, and facilitated a legal and compliance workshop covering every piece of calculator copy, disclosure, and pre-qualification error message — replacing dead-end errors with actionable recovery paths so customers could confidently work through roadblocks and personalize their financing.
Develop
Independently led evaluative A/B testing with recent car buyers, using the findings to challenge the team's own assumptions — most notably, replacing a dropdown-based settings layout with tabs after testing showed it was faster to scan. Built highly scalable Figma components covering every calculator configuration for both calculator variants and pressure-tested across all responsive breakpoints and host platforms ahead of handoff.
Deliver
The redesigned calculator shipped a 165% increase in price-breakdown interactions and a 9.41% increase in CTA click-conversion rate. The Tier 1 calculator strategy delivered on schedule for its April target, directly shaping leadership's product roadmap. As a side effort, introduced Gemini Canvas into the design workflow to rapidly prototype a new recommended-products UI pattern and align product partners in two weeks — a practice later adopted team-wide.
Impact
By reducing the size of the calculator and updating the design with our brand refresh, dealers can provide this payment estimator tool for their customers to better understand their financing. Car buyers gain clarity on their financing options and customized rates while receiving helpful, actionable recovery paths if errors occur. This smaller, modern design drove a 165% spike in calculator interactions and boosted dealer CTA conversions by 9.41%.
Reusable component library shortened delivery time on a second calculator product · new AI-assisted prototyping workflow scaled org-wide
RECOMMENDATIONS FROM THE TEAM
"I had a great experience working alongside Linh-Hoa at Capital One. She led the UI/UX redesign of our customer facing application to assist car buyers during their car buying journey, ultimately increasing conversion rates by 9.5%. She efficiently performed customer research to gather insights on ways to adjust our UI and translated the feedback into actionable UI changes. She also leveraged AI tools to quickly showcase alternative design ideas, and quickly set up a site for our engineers to submit their own practical ideas for redesigns. I really enjoyed the open collaboration between design and development. Overall, Linh-Hoa is a very strong designer, with great problem solving and communication skills, and is a joy to work with."
-Johnny Nguyen, Software Engineer at Capital One
