I won the Microsoft Excel World Championship. Here’s what every office worker should know about Excel.

This as-told-to essay is based on a conversation with Diarmuid Early, the 40-year-old winner of the 2025 Microsoft Excel World Championship. It’s been edited for length and clarity.

I’ve been in the Excel business for about 20 years.

I played around with it a little bit in college and started using it professionally at Boston Consulting Group. Then I spent 10 years at Deutsche Bank as a business manager. It was lots of data analysis and reporting on financials.

I’ve been doing my own thing for about six years now, so I’ve pretty much used Excel my entire career.

Winning the Excel World Championship felt great. I’ve been a long-term underperformer in the postseason. I’ve been first or second seed going into the knockouts every year. I’ve made it to the final stage in Las Vegas the last couple of years, but I think fifth was my best finish before.

My top Excel tip

My number one tip for office workers is…