How do I write a UX case study?

Most case studies are a gallery of final screens with a paragraph of process words on top. Hiring managers have seen thousands. They skim, and they look for one thing: how you think.

Nielsen Norman Group interviewed hiring managers for their portfolio advice, and one line sums it up: "Don't just show me the finished product." They also note that very few reviewers read a portfolio word for word, so the structure has to carry the story for someone who only scans.

NN/g lists seven things a case study should cover. I use the same skeleton:

1. The problem. What was broken, for whom, and how you knew.
2. Your role. What you did versus the team. Be specific; vague "we" reads as hiding.
3. How you got to the solution. Research, options, the reasoning in between.
4. How the solution solves the problem. Connect the final design back to point 1.
5. Challenges. Constraints, and the ideas you killed and why.
6. The impact. What changed for users and for the business.
7. What you learned. One honest sentence beats a paragraph of humility.

They recommend three to five strong projects over many weak ones. Quality over quantity.

Products start with the problem, not the design. The fastest way to prove you think that way is to tie the work to a metric.

A real example from my own work: I ran a Mixpanel funnel analysis across 1.13M signups and found a segment converting at 0.43% against a 1.04% baseline, then designed and shipped a fix aimed at that segment.

Notice what that sentence does. It names the scale, the problem, and the evidence in one line, before a single screenshot. If you do not have big numbers, small ones still work: "three of five users could not find the save button" is a problem statement a hiring manager respects.

• Write a three-line summary at the top: problem, your role, outcome. Some reviewers will read only this.
• Use headings a skimmer can follow, like the seven above.
• Show the messy middle visually: sketches, flows, before and after, annotated screenshots.
• Keep text short next to images. One idea per paragraph.
• Decide your three takeaways first, then cut anything that does not support them.

1. Pick your strongest project and write only the three-line summary first.
2. Find one number, even a small one, that shows the problem or the outcome.
3. Rebuild the case study with the template above, then ask one designer to skim it in 60 seconds and tell you what they remember.

For the bigger picture of what goes in a portfolio, read my portfolio guide. To practise presenting it, see the interviews guide.