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 to believe that there is a better way.
Whenever you find, ‘Oh god, I’ve been copying and pasting this for the last 10 minutes, and I still have 15 minutes to go,’ whenever you find yourself doing something that is manual and repetitive, it is very likely that Excel has a better way to do it.
It is very likely that, if you ask Google or ChatGPT a brief description of what you need, 1,000 or more other people have wanted to do the same thing over the years.
In my experience, 80% of the things I’ve ever struggled with in Excel, if I Google it with a reasonably crisp description, there’s a post out there somewhere saying how to do it.
Microsoft Excel World Championship
Learning to use the SUMIFS function is probably going to take you longer the first time than just doing it yourself. But it’s going to be a little bit faster the second time, a lot faster the third time, and one bajillion times faster over the thousand times you have to do it over your career.
It’s also much less likely to be wrong or have unexplainable errors that you will get if you’re doing it manually.
It’ll take you a little longer the first time, but if you’re the most junior, new employee at a company, they kind of expect you to be stupid and take ages to do things. If you are stupid and take ages the first time, and the second time you do it 10 times faster, the payoff over six months, not to mention your career, is pretty huge.
As you start to learn more of those things and start to stitch them together to do more complex things, the payoff is exponential.
With the time you save, take a step back
It’s great to be able to very, very quickly zoom through and say, “The answer is seven.” If you get to that quickly, you get more time to say: “Does it make any sense that the answer is seven?”
It’s the thing that the junior bankers, the junior consultants, are least likely to do. They see it as their job to turn the crank on the model, hand over the answer, and the next person above them on the chain says: What does this mean? What’s the insight? Does it make sense?
Taking the time to do that yourself and then communicating that gets you a lot more credibility. It also makes you a lot more likely to spot your own stupid mistakes until someone spots them for you.
Screenshot via Microsoft Excel World Championship
The thing that I find most horrifying is when I see a formula that is 50 different numbers together in the form: A1 + B3 + C5 + D10. Someone has obviously hand-typed them all or, plus click plus click plus click.
The amount of time that takes, and the chances that you will misclick one time and have something wrong you’ll never be able to find, is really high.
That’s one of the more entry-level ways to go down a dark path. There’s basically, at every level of Excel skill, there’s the thing you’re doing wrong that you don’t realize you’re doing wrong until you get to the next level. There are problems all the way up.
When it gets there, I think AI will be very helpful in taking people from bad to not bad, or maybe even bad to good. It’s probably not going to be much help to people like me who are already quite experienced.
If it gets to a level where it can teach me new things in Excel, then there’s not much room left for human Excel users.
I’ve got 50,000 hacks. I used to do a lot of Excel training in my BCG days. Every now and again you would teach someone something, and you’d see this look of combined joy and horror on their face. You subsequently find out: “This is the thing that, if I knew this last night, I would not have had to work until 2 a.m..”
That is the person who will never forget what you just taught them.
