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Mint Number

User Goal

Find an easy, yet powerful, way to track my budget.

Business Goal

Mint’s budget feature has low engagement, even though it is the most wanted feature. Mint wants to reinvent the solution to improve user acquisition and engagement.


Strategic planning, interaction design, research and visual design.

Success Metrics

87% of users completed the whole categorization phase, versus 2.5% in Mint’s budget application. User re-engagements increased to 44% from 15%.

Product solution

Apply a simple mechanism to categorize "needs" (fixed expenses) versus "wants" (flexible expenses), before users drop off. Calculate a single Mint number as a daily spending allowance. This solution was created for users who have trouble controlling their discretionary spending and would like an easier way to manage their expenditures.

Current flow problems

currently flow

Survey on top wanted features

30% of users want to see what’s left to spend Mint top feature

Conduct user interview

I talked to users to understand their spending behaviors and how they managed their money from a day-to-day perspective. Mint interview

User pain points

Mint Number amy image
  • Amy wants to control her constant temptations to spend.
  • Amy only has a $100-$200 left at the end of the month, causing an extremely stressful situation.
  • Amy is finding it difficult to track her budget and is feeling overwhelmed.

Amy's income and expenses

It was difficult for Amy to figure out what is left to spend.


Idea explorations

Idea 1: 50(needs)/30(Wants)/20(Savings)

Elizabeth Warren popularized the "50/20/30 budget rule". It is an easy way to allocate spending based on needs, wants, and savings. Mint number idea 1

Idea 2: Make it fun

Focus on millennials. Gamify the whole budgeting experience. Use passes/cards instead of money to limit spending every month and create a leaderboard to compete with friends.

Mint number idea 2

Idea 3: Financial scale

Daily “left to spend” number gives users an allowance to spend every day. This number is self-adjusted, based on what is spent that day. AMint number idea 3

Team work

Shared work, generated ideas, and got feedback from cross-functional teams.

Team Work

Lean experiment map

This map helped us document various experiments and share iteration stories about what experiments have been shipped and what insights were learned.

Lean Experiment map

Final design


Prototype demo



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